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# Veritas Prep PS Forum Expert - Karishma - Ask Me Anything about Math

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Veritas Prep GMAT Instructor
Joined: 16 Oct 2010
Posts: 9705
Location: Pune, India

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01 Dec 2018, 02:31
vishuvashishth wrote:
Hi Karishma,
Thanks for replying to my PM. As suggested , i am pasting URL's of few word problems to start with. I will be sharing lot of problems soon but i will wait for you to sort them out and help me to see how I could have converted it into an equation. After a few, may be I will start seeing how to convert into equations on my own.

https://gmatclub.com/forum/of-the-stude ... 95246.html
http://gmatclub.com/forum/working-simul ... 07314.html
http://gmatclub.com/forum/in-order-to-c ... 40555.html
https://gmatclub.com/forum/gmat-diagnos ... 79356.html
https://gmatclub.com/forum/gmat-diagnos ... 79358.html
https://gmatclub.com/forum/a-chess-play ... 52608.html
https://gmatclub.com/forum/if-x-a-and-b ... 01946.html

Sure, I will help you out on any questions you might have.
Note that not every question given by you will involve making equations. But I will go one line at a time and show you how to evaluate it to arrive at the answer.

Here is the first one: https://gmatclub.com/forum/of-the-stude ... l#p2182147
_________________
Karishma
Veritas Prep GMAT Instructor

Veritas Prep GMAT Instructor
Joined: 16 Oct 2010
Posts: 9705
Location: Pune, India

### Show Tags

01 Dec 2018, 02:49
vishuvashishth wrote:
Hi Karishma,
Thanks for replying to my PM. As suggested , i am pasting URL's of few word problems to start with. I will be sharing lot of problems soon but i will wait for you to sort them out and help me to see how I could have converted it into an equation. After a few, may be I will start seeing how to convert into equations on my own.

https://gmatclub.com/forum/of-the-stude ... 95246.html
http://gmatclub.com/forum/working-simul ... 07314.html
http://gmatclub.com/forum/in-order-to-c ... 40555.html
https://gmatclub.com/forum/gmat-diagnos ... 79356.html
https://gmatclub.com/forum/gmat-diagnos ... 79358.html
https://gmatclub.com/forum/a-chess-play ... 52608.html
https://gmatclub.com/forum/if-x-a-and-b ... 01946.html

No. 3

https://gmatclub.com/forum/in-order-to- ... l#p2182154

This doesn't involve forming equations either. In fact, there are very few questions in which you will need to actually form an equation and then solve it. Notice the way you should evaluate this sentence to get to the answer.
_________________
Karishma
Veritas Prep GMAT Instructor

Current Student
Joined: 04 Jun 2018
Posts: 156
GMAT 1: 610 Q48 V25
GMAT 2: 690 Q50 V32
GMAT 3: 710 Q50 V36

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01 Dec 2018, 02:49
Question 2: A group of 10 people consists of 2 married couples and 6 bachelors. A committee of 4 is to be selected from the 10 people. How many different committees can be formed if the committee can consist of at most one married couple?

Solution: We have to select 4 people out of: 6 bachelors and 2 married couples.

The number of ways of selecting any 4 people out of 10 is 10*9*8*7/4! = 210 (Note here that we are just selecting 4 people. We are not arranging them so we divide by 4!)

The people will get selected in various ways:

1. Four bachelors
2. One from a couple and three bachelors
3. Two from two different couples and two bachelors
4. One couple and two bachelors
5. One couple, one person from a couple, one bachelor
6. Two couples

If we add the number of committees possible in each of these cases, we will get 210. Out of all these cases, only the last one (two couples) has more than one married couple. Instead of calculating the number of different committees that can be formed in each of the first five cases, we can calculate the number of committees in the last case and subtract it from 210.

How many different committees can be formed such that there are 2 couples? Only one since we have only 2 couples. We will have to select both the couples and we will get 4 people.

Number of different committees of 4 people such that there is at most one married couple = 210 – 1 = 209.

Just for practice, let’s see how we can calculate the different number of committees that can be formed in each of the first five cases. The sum of all these cases should give us 209.

1. Select 4 bachelors from 6 bachelors in 6*5*4*3/4! = 15 different committees
2. Select 1 person out of the two couples (4 people) in 4 ways and 3 bachelors from 6 bachelors in 6*5*4/3! = 20 ways. So you select the 4 people in 4*20 = 80 different committees
3. Select 2 people from 2 different couples in 4*2/2! = 4 ways and 2 bachelors from 6 bachelors in 6*5/2! = 15 ways. So you select the 4 people in 4*15 = 60 different committees
4. Select 1 couple in 2 ways and 2 bachelors from 6 bachelors in 6*5/2! = 15 ways. So you select the 4 people in 2*15 = 30 different committees
5. Select 1 couple in 2 ways, 1 person from the remaining couple in 2 ways and 1 bachelor from 6 bachelors in 6 ways. So you can select the 4 people in 2*2*6 = 24 different committees

The sum of all these five cases = 15 + 80 + 60 + 30 + 24 = 209 different committees

First of all,Thanks for making these articles.

Now I have a slight doubt related to above question .

4. Select 1 couple in 2 ways and 2 bachelors from 6 bachelors in 6*5/2! = 15 ways. So you select the 4 people in 2*15 = 30 different committees
5. Select 1 couple in 2 ways, 1 person from the remaining couple in 2 ways and 1 bachelor from 6 bachelors in 6 ways. So you can select the 4 people in 2*2*6 = 24 different committees

When I was doing the question, I considered 5 and 6 to be symmetrical cases.
I calculated it as follows:
2c1(1 married couple selected) +
2c1(One member of the other married couple selected) +
7c2(selected 2 members out of a group of 7)

= 84 ways

Now i do realise that I am counting something twice. But I can't exactly point out where.
Can you please tell me where I am going wrong, and If I were to proceed with my method, what should I have subtracted to get a correct answer.

Hope to hear from you soon!

Regards
Nitesh
Veritas Prep GMAT Instructor
Joined: 16 Oct 2010
Posts: 9705
Location: Pune, India

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01 Dec 2018, 02:53
vishuvashishth wrote:
Hi Karishma,
Thanks for replying to my PM. As suggested , i am pasting URL's of few word problems to start with. I will be sharing lot of problems soon but i will wait for you to sort them out and help me to see how I could have converted it into an equation. After a few, may be I will start seeing how to convert into equations on my own.

https://gmatclub.com/forum/of-the-stude ... 95246.html
http://gmatclub.com/forum/working-simul ... 07314.html
http://gmatclub.com/forum/in-order-to-c ... 40555.html
https://gmatclub.com/forum/gmat-diagnos ... 79356.html
https://gmatclub.com/forum/gmat-diagnos ... 79358.html
https://gmatclub.com/forum/a-chess-play ... 52608.html
https://gmatclub.com/forum/if-x-a-and-b ... 01946.html

I have already solved no 2 by the variation method. I have also provided the link to my relevant post there.
You can also solve it using unitary method as shown by some people there (if 10 workers make 50 chairs, 1 worker will make 5 chairs so 18 workers will make 18*5 chairs etc). But I prefer the simple and straight forward method shown by me. Once you understand it, it takes a few seconds to implement.
_________________
Karishma
Veritas Prep GMAT Instructor

Veritas Prep GMAT Instructor
Joined: 16 Oct 2010
Posts: 9705
Location: Pune, India

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01 Dec 2018, 04:37
nitesh50 wrote:

Q. IN how many ways can A,B,C,D,E,F be arranged in a circular table provided that A cannot sit next to D or E?

This question is a slight variation in comparison to your question on the Combinations Article 3: Circular Arrangements.

I recon that it is slightly complicated.

Here was my approach:

If only
1. D/E is selected: 2 ways * 6 ways( 3c2 ways of choosing people to be beside A and 2! ways of arranging them) * 2 ways( the other people arrangement)

2. D and E both are selected:
3c2(out of remaining 3 people, 2 are selected)* 2 ways (those 2 people are arranged) * 2 (D,E are arranged in remaining places)

3. A is not selected: 4!

SO total possibilities:

24+ 12+24= 60 ways.

Am i correct in my reasoning ?
and is there any simpler and faster way to do this question?

Regards
Nitesh

Hey Nitesh,

I am not sure what your question is. There are two variations possible:

Q. IN how many ways can A,B,C,D,E,F be arranged in a circular table provided that A cannot sit next to D and E at the same time. (Implying that A sitting next to D if E is far away is ok)
or
Q. IN how many ways can A,B,C,D,E,F be arranged in a circular table provided that A can sit next to neither D nor E? (Implying that both D and E should be far away from A)

The first question is discussed as question 2 in my post:

Question 2: There are 6 people, A, B, C, D, E and F. They have to sit around a circular table such that A cannot sit next to D and F at the same time. How many such arrangements are possible?

Solution: Total number of ways of arranging 6 people in a circle = 5! = 120

Now, A cannot sit next to D and F simultaneously.

Let’s first find the number of arrangements in which A sits between D and F. In how many of these 120 ways will A be between D and F? Let’s consider that D, A and F form a single unit. We make DAF sit on any three consecutive seats in 1 way and make other 3 people sit in 3! ways (since the rest of the 3 seats are distinct). But D and F can swap places so the number of arrangements will actually be 2*3! = 12

In all, we can make A sit next to D and F simultaneously in 12 ways.

The number of arrangements in which A is not next to D and F simultaneously is 120 – 12 = 108.

The second question is discussed as Question 3 in my post:

Question 3: There are 6 people, A, B, C, D, E and F. They have to sit around a circular table such that A can sit neither next to D nor next to F. How many such arrangements are possible?

Solution: In the previous question, A could sit next to D and F; the only problem was that A could not sit next to both of them at the same time. Here, A can sit next to neither D nor F. Generally, it is difficult to wrap your head around what someone cannot do. It is easier to consider what someone can do and go from there. A cannot sit next to D and F so he will sit next to two of B, C and E.

Let’s choose two out of B, C and E. In other words, let’s drop one of B, C and E. We can drop one of B, C and E in 3 ways (we can drop B or C or E). This means, we can choose two out of B, C and E in 3 ways (We will come back to choosing 2 people out of 3 when we work on combinations). Now, we can arrange the two selected people around A in 2 ways (say we choose B and C. We could have BAC or CAB). We make these three sit on any three consecutive seats in 1 way.

Number of ways of choosing two of B, C and E and arranging the chosen two with A = 3*2 = 6

The rest of the three people can sit in three distinct seats in 3! = 6 ways

Total number of ways in which A will sit next to only B, C or E (which means A will sit neither next to D nor next to F) = 6*6 = 36 ways

https://www.veritasprep.com/blog/2011/1 ... ts-part-i/

_________________
Karishma
Veritas Prep GMAT Instructor

Veritas Prep GMAT Instructor
Joined: 16 Oct 2010
Posts: 9705
Location: Pune, India

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01 Dec 2018, 05:00
vishuvashishth wrote:
Hi Karishma,
Thanks for replying to my PM. As suggested , i am pasting URL's of few word problems to start with. I will be sharing lot of problems soon but i will wait for you to sort them out and help me to see how I could have converted it into an equation. After a few, may be I will start seeing how to convert into equations on my own.

https://gmatclub.com/forum/of-the-stude ... 95246.html
http://gmatclub.com/forum/working-simul ... 07314.html
http://gmatclub.com/forum/in-order-to-c ... 40555.html
https://gmatclub.com/forum/gmat-diagnos ... 79356.html
https://gmatclub.com/forum/gmat-diagnos ... 79358.html
https://gmatclub.com/forum/a-chess-play ... 52608.html
https://gmatclub.com/forum/if-x-a-and-b ... 01946.html

No 4

A cook went to a market to buy some eggs and paid $12. But since the eggs were quite small, he talked the seller into adding two more eggs, free of charge. As the two eggs were added, the price per dozen went down by a dollar. How many eggs did the cook bring home from the market? A. 8 B. 12 C. 15 D. 16 E. 18 Say price per dozen was P and it became (P - 1) due to the extra 2 eggs. Say he bought D dozens and the extra 2 eggs made it (D + 2/12) dozens. Now note that total paid by him in both cases is$12

PD = 12
and
(P - 1)(D + 1/6) = 12

PD + P/6 - D - 1/6 = 12
Putting PD = 12 from above we get: P - 6D = 1
Putting P = 12/D from above, we get: 12/D - 6D = 1

Now solve for D to get:
12 - 6D^2 = D
6D^2 + D - 12 = 0
6D^2 + 9D - 8D - 12 = 0
3D(2D + 3) - 4(2D + 3) = 0
(2D + 3)*(3D - 4) = 0
So D = - 3/2 or 4/3

Since D must be positive, it should be 4/3. He brought home (4/3)*12 + 2 = 18 eggs
_________________
Karishma
Veritas Prep GMAT Instructor

Veritas Prep GMAT Instructor
Joined: 16 Oct 2010
Posts: 9705
Location: Pune, India

### Show Tags

01 Dec 2018, 05:43
vishuvashishth wrote:
Hi Karishma,
Thanks for replying to my PM. As suggested , i am pasting URL's of few word problems to start with. I will be sharing lot of problems soon but i will wait for you to sort them out and help me to see how I could have converted it into an equation. After a few, may be I will start seeing how to convert into equations on my own.

https://gmatclub.com/forum/of-the-stude ... 95246.html
http://gmatclub.com/forum/working-simul ... 07314.html
http://gmatclub.com/forum/in-order-to-c ... 40555.html
https://gmatclub.com/forum/gmat-diagnos ... 79356.html
https://gmatclub.com/forum/gmat-diagnos ... 79358.html
https://gmatclub.com/forum/a-chess-play ... 52608.html
https://gmatclub.com/forum/if-x-a-and-b ... 01946.html

No 5:

Mac can finish a job in M days and Jack can finish the same job in J days. After working together for T days, Mac left and Jack alone worked to complete the remaining work in R days. If Mac and Jack completed an equal amount of work, how many days would have it taken Jack to complete the entire job working alone?

(1) M = 20 days
(2) R = 10 days

Rate of work of Mac = 1/M (since it takes him M days to finish 1 work and Rate = Work/Time)
Rate of work of Jack = 1/J (since it takes him J days to finish 1 work and Rate = Work/Time)

Mac worked for T days and did half the work so as per Work = Rate*Time, 1/2 = T/M
Jack worked for (T + R) days and did half the work so as per Work = Rate*Time, 1/2 = (T+R)/J

We need the value of J.

(1) M = 20 days
1/2 = T/20
T = 10 days

1/2 = (10 + R)/J
Two unknowns and 1 equation. Not possible to solve.

(2) R = 10 days
1/2 = (T+10)/J
Two unknowns and 1 equation. Not possible to solve.

Using both, 1/2 = (10 + 10)/J
J = 40 days
Sufficient
_________________
Karishma
Veritas Prep GMAT Instructor

Current Student
Joined: 04 Jun 2018
Posts: 156
GMAT 1: 610 Q48 V25
GMAT 2: 690 Q50 V32
GMAT 3: 710 Q50 V36

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01 Dec 2018, 23:50

Question 1: There are x children and y chairs in a room where x and y are prime numbers. In how many ways can the x children be seated in the y chairs (assuming that each chair can seat exactly one child)?

Statement 1: x + y = 12
Statement 2: There are more chairs than children.

Solution:

There are x children and y chairs.

x and y are prime numbers.

Statement 1: x + y = 12

Since x and y are prime numbers, a quick run on 2, 3, 5 shows that there are two possible cases:

Case 1: x=5 and y=7

There are 5 children and 7 chairs.

Case 2: x=7 and y=5

There are 7 children and 5 chairs

At first glance, they might look like two different cases and you might feel that statement 1 is not sufficient alone. But note that the question doesn’t ask you for number of children or number of chairs. It asks you about the number of arrangements.

Case 1: x=5 and y=7

If there are 5 children and 7 chairs, we select 5 chairs out of the 7 in 7C5 ways. We can now arrange 5 children in 5 seats in 5! ways.

Total number of arrangements would be 7C5 * 5!

Case 2: x = 7 and y = 5

If there are 7 children and 5 chairs, we select 5 children out of the 7 in 7C5 ways. We can now arrange 5 children in 5 seats in 5! ways.

Total number of arrangements would be 7C5 * 5!

Note that in both cases the number of arrangements is 7C5*5!. Combinatorics does not distinguish between people and things. 7 children on 5 seats is the same as 5 children on 7 seats because in each case you have to select 5 out of 7 (either seats or children) and then arrange 5 children in 5! ways.

So actually this statement alone is sufficient! Most people would not have seen that coming!

Statement 2: There are more chairs than people.

We don’t know how many children or chairs there are. This statement alone is not sufficient.

Answer: A This question is discussed HERE.

We were tempted to answer the question as (C) but it was way too easy. Statement 1 gave 2 cases and statement 2 narrowed it down to 1. Be aware that if it looks too easy, you are probably missing something!

Now, what if we alter the question slightly and make it:

Question 2: There are x children and y chairs arranged in a circle in a room where x and y are prime numbers. In how many ways can the x children be seated in the y chairs (assuming that each chair can seat exactly one child)?

Statement 1: x + y = 12
Statement 2: There are more chairs than children

This question is part of your articles on P/c.

My doubt:
If we are asked to arrange 7 children in 5 chairs, then this case is not possible.(provided that every chair can have 1 child only)
There is no possibility in which all 7 children can be arranged in 5 chairs.

Similarly, when I was doing Q1 stated above, I inferred from the question statement that the number of children has to be less than/equal to the number of chairs.

Hence the case in which we have 7 children and 5 chairs becomes impossible.

Similarly in Q2, we cannot arrange 7 children in 5 chairs arranged in a circular manner.
Hence the answer should be A.

Is my stated reasoning correct?
Or am I missing something?

Regards
Nitesh
Veritas Prep GMAT Instructor
Joined: 16 Oct 2010
Posts: 9705
Location: Pune, India

### Show Tags

03 Dec 2018, 00:22
vishuvashishth wrote:
Thanks for replying to my PM. As suggested , i am pasting URL's of few word problems to start with. I will be sharing lot of problems soon but i will wait for you to sort them out and help me to see how I could have converted it into an equation. After a few, may be I will start seeing how to convert into equations on my own.

https://gmatclub.com/forum/of-the-stude ... 95246.html
http://gmatclub.com/forum/working-simul ... 07314.html
http://gmatclub.com/forum/in-order-to-c ... 40555.html
https://gmatclub.com/forum/gmat-diagnos ... 79356.html
https://gmatclub.com/forum/gmat-diagnos ... 79358.html
https://gmatclub.com/forum/a-chess-play ... 52608.html
https://gmatclub.com/forum/if-x-a-and-b ... 01946.html

Last two questions:
https://gmatclub.com/forum/a-chess-play ... l#p2183020
https://gmatclub.com/forum/if-x-a-and-b ... l#p2183015
_________________
Karishma
Veritas Prep GMAT Instructor

Veritas Prep GMAT Instructor
Joined: 16 Oct 2010
Posts: 9705
Location: Pune, India

### Show Tags

03 Dec 2018, 00:32
nitesh50 wrote:
When I was doing the question, I considered 5 and 6 to be symmetrical cases.
I calculated it as follows:
2c1(1 married couple selected) +
2c1(One member of the other married couple selected) +
7c2(selected 2 members out of a group of 7)

= 84 ways

Now i do realise that I am counting something twice. But I can't exactly point out where.
Can you please tell me where I am going wrong, and If I were to proceed with my method, what should I have subtracted to get a correct answer.

Hope to hear from you soon!

Regards
Nitesh

The two cases are different. A couple and 2 bachelors vs a couple, one from another couple and a bachelor.
In your calculation, you are selecting 5 people - 1 married couple selected (2 people) + One member of the other married couple selected + selected 2 members out of a group of 7 = 5 people selected

Also, from where did you get the group of 7?
_________________
Karishma
Veritas Prep GMAT Instructor

Veritas Prep GMAT Instructor
Joined: 16 Oct 2010
Posts: 9705
Location: Pune, India

### Show Tags

03 Dec 2018, 00:50
nitesh50 wrote:

Question 1: There are x children and y chairs in a room where x and y are prime numbers. In how many ways can the x children be seated in the y chairs (assuming that each chair can seat exactly one child)?

Statement 1: x + y = 12
Statement 2: There are more chairs than children.

Solution:

There are x children and y chairs.

x and y are prime numbers.

Statement 1: x + y = 12

Since x and y are prime numbers, a quick run on 2, 3, 5 shows that there are two possible cases:

Case 1: x=5 and y=7

There are 5 children and 7 chairs.

Case 2: x=7 and y=5

There are 7 children and 5 chairs

At first glance, they might look like two different cases and you might feel that statement 1 is not sufficient alone. But note that the question doesn’t ask you for number of children or number of chairs. It asks you about the number of arrangements.

Case 1: x=5 and y=7

If there are 5 children and 7 chairs, we select 5 chairs out of the 7 in 7C5 ways. We can now arrange 5 children in 5 seats in 5! ways.

Total number of arrangements would be 7C5 * 5!

Case 2: x = 7 and y = 5

If there are 7 children and 5 chairs, we select 5 children out of the 7 in 7C5 ways. We can now arrange 5 children in 5 seats in 5! ways.

Total number of arrangements would be 7C5 * 5!

Note that in both cases the number of arrangements is 7C5*5!. Combinatorics does not distinguish between people and things. 7 children on 5 seats is the same as 5 children on 7 seats because in each case you have to select 5 out of 7 (either seats or children) and then arrange 5 children in 5! ways.

So actually this statement alone is sufficient! Most people would not have seen that coming!

Statement 2: There are more chairs than people.

We don’t know how many children or chairs there are. This statement alone is not sufficient.

Answer: A This question is discussed HERE.

We were tempted to answer the question as (C) but it was way too easy. Statement 1 gave 2 cases and statement 2 narrowed it down to 1. Be aware that if it looks too easy, you are probably missing something!

Now, what if we alter the question slightly and make it:

Question 2: There are x children and y chairs arranged in a circle in a room where x and y are prime numbers. In how many ways can the x children be seated in the y chairs (assuming that each chair can seat exactly one child)?

Statement 1: x + y = 12
Statement 2: There are more chairs than children

This question is part of your articles on P/c.

My doubt:
If we are asked to arrange 7 children in 5 chairs, then this case is not possible.(provided that every chair can have 1 child only)
There is no possibility in which all 7 children can be arranged in 5 chairs.

Similarly, when I was doing Q1 stated above, I inferred from the question statement that the number of children has to be less than/equal to the number of chairs.

Hence the case in which we have 7 children and 5 chairs becomes impossible.

Similarly in Q2, we cannot arrange 7 children in 5 chairs arranged in a circular manner.
Hence the answer should be A.

Is my stated reasoning correct?
Or am I missing something?

Regards
Nitesh

Nitesh, the case of 7 children and 5 chairs is no different. You select 5 of the 7 children and make them sit on the 5 chairs. 2 children will be left standing.
Just like in the case of 7 chairs and 5 children, you select 5 of the 7 chairs and arrange the 5 children in the 5 chairs. 2 chairs will be vacant.

Both cases are about selecting 5 out of distinct 7 and matching them with other distinct 5.
_________________
Karishma
Veritas Prep GMAT Instructor

Senior Manager
Joined: 20 Mar 2018
Posts: 372
Location: Ghana
Concentration: Finance, Real Estate

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03 Dec 2018, 06:57
Hello Karishma ,wana know why is I got this question wrong
If Yury has been writing programming code for 14hrs at a rate of 5 lines of code per 20sec. How many lines of code has he written?
I used the work rate formula =R*T so w=5/20*14hrs =3.5 and it was wrong where lies my reasoning?
Thank you

Sent from my iPhone using GMAT Club Forum mobile app
Senior Manager
Joined: 20 Mar 2018
Posts: 372
Location: Ghana
Concentration: Finance, Real Estate

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03 Dec 2018, 13:27
Hello Karishma is there a tag on GC which I can find your post or solutions only ,to questions,yours seems fast and sweet
Also what is the efficient way to tackle any word problem? Is it
1.Read the question throughout without writing any thing and understand what is being asked before going back to the question to note each statement for creating equations
2.Go straight to what was asked? Noting it and coming back to read the question noting each statement with what was asked in mind
3.Right away note each statement you read and start creating equations before you get to what was asked . Please which is the best or if none is,Kindly suggest because am really struggling with word problems

Sent from my iPhone using GMAT Club Forum mobile app
Veritas Prep GMAT Instructor
Joined: 16 Oct 2010
Posts: 9705
Location: Pune, India

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04 Dec 2018, 04:32
1
Staphyk wrote:
Hello Karishma ,wana know why is I got this question wrong
If Yury has been writing programming code for 14hrs at a rate of 5 lines of code per 20sec. How many lines of code has he written?
I used the work rate formula =R*T so w=5/20*14hrs =3.5 and it was wrong where lies my reasoning?
Thank you

Sent from my iPhone using GMAT Club Forum mobile app

The units need to match.

Rate = 5 lines/ 20 sec
Time = 14 hrs = 14*60*60 sec

$$Work = \frac{5 lines}{20 secs} * 14*60*60 secs = 12600 lines$$
_________________
Karishma
Veritas Prep GMAT Instructor

Veritas Prep GMAT Instructor
Joined: 16 Oct 2010
Posts: 9705
Location: Pune, India

### Show Tags

04 Dec 2018, 05:18
1
Staphyk wrote:
Hello Karishma is there a tag on GC which I can find your post or solutions only ,to questions,yours seems fast and sweet
Also what is the efficient way to tackle any word problem? Is it
1.Read the question throughout without writing any thing and understand what is being asked before going back to the question to note each statement for creating equations
2.Go straight to what was asked? Noting it and coming back to read the question noting each statement with what was asked in mind
3.Right away note each statement you read and start creating equations before you get to what was asked . Please which is the best or if none is,Kindly suggest because am really struggling with word problems

Sent from my iPhone using GMAT Club Forum mobile app

Staphyk,

You can put my name in the author field of the Advanced Search feature of GC and search for all my posts in whichever forum you wish to:

Different word problems require different approaches. I do favour going one line at a time and evaluating each till I reach the question stem. Here are some recent solutions:
https://gmatclub.com/forum/of-the-stude ... l#p2182147
https://gmatclub.com/forum/in-order-to- ... l#p2182154

Sometimes, you will need to consider the entire question to form equations:
https://gmatclub.com/forum/veritas-prep ... l#p2182196
_________________
Karishma
Veritas Prep GMAT Instructor

Senior Manager
Joined: 20 Mar 2018
Posts: 372
Location: Ghana
Concentration: Finance, Real Estate

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04 Dec 2018, 05:42
Staphyk wrote:
Hello Karishma is there a tag on GC which I can find your post or solutions only ,to questions,yours seems fast and sweet
Also what is the efficient way to tackle any word problem? Is it
1.Read the question throughout without writing any thing and understand what is being asked before going back to the question to note each statement for creating equations
2.Go straight to what was asked? Noting it and coming back to read the question noting each statement with what was asked in mind
3.Right away note each statement you read and start creating equations before you get to what was asked . Please which is the best or if none is,Kindly suggest because am really struggling with word problems

Sent from my iPhone using GMAT Club Forum mobile app

Staphyk,

You can put my name in the author field of the Advanced Search feature of GC and search for all my posts in whichever forum you wish to:

Different word problems require different approaches. I do favour going one line at a time and evaluating each till I reach the question stem. Here are some recent solutions:
https://gmatclub.com/forum/of-the-stude ... l#p2182147
https://gmatclub.com/forum/in-order-to- ... l#p2182154

Sometimes, you will need to consider the entire question to form equations:
https://gmatclub.com/forum/veritas-prep ... l#p2182196
Thank you

Sent from my iPhone using GMAT Club Forum mobile app
Senior Manager
Joined: 20 Mar 2018
Posts: 372
Location: Ghana
Concentration: Finance, Real Estate

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04 Dec 2018, 05:48
Please I can I get the verbal forum since here is strictly Quant
Like Veritas STOP strategy

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Senior Manager
Joined: 20 Mar 2018
Posts: 372
Location: Ghana
Concentration: Finance, Real Estate

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04 Dec 2018, 12:00
2 men and 3 women can finish a piece of work in 10 days. while 4 men can do it in 10 days. how many days can 3 men and 3 women take to finish the same work??

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Veritas Prep GMAT Instructor
Joined: 16 Oct 2010
Posts: 9705
Location: Pune, India

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04 Dec 2018, 23:58
Staphyk wrote:
Please I can I get the verbal forum since here is strictly Quant
Like Veritas STOP strategy

Sent from my iPhone using GMAT Club Forum mobile app

Sure Staphyk, here is the link to my CR thread. You can put the link of specific CR posts there and I will get to them.
https://gmatclub.com/forum/veritas-prep ... 78026.html

Also, the search link I gave you above works for all forums. Go down in the forums window and you will see the Verbal forums too there.
_________________
Karishma
Veritas Prep GMAT Instructor

Veritas Prep GMAT Instructor
Joined: 16 Oct 2010
Posts: 9705
Location: Pune, India

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05 Dec 2018, 00:06
Staphyk wrote:
2 men and 3 women can finish a piece of work in 10 days. while 4 men can do it in 10 days. how many days can 3 men and 3 women take to finish the same work??

Sent from my iPhone using GMAT Club Forum mobile app

2 men and 3 women finish it in 10 days
4 men (2 men + 2 men) finish it in 10 days

So 3 women are equivalent to 2 men.

Then 3 men and 3 women are equivalent to 3 men and 2 men i.e. 5 men.

Now, 4 men complete the job in 10 days.
So 5 men will take 10*(4/5) = 8 days (fewer days will be taken so multiply by 4/5, the fraction less than 1)

For more on this method, check this post: https://www.veritasprep.com/blog/2015/1 ... made-easy/
_________________
Karishma
Veritas Prep GMAT Instructor

Re: Veritas Prep PS Forum Expert - Karishma - Ask Me Anything about Math   [#permalink] 05 Dec 2018, 00:06

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