GMAT Question of the Day - Daily to your Mailbox; hard ones only

 It is currently 23 Jan 2019, 19:01

### GMAT Club Daily Prep

#### Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.

Customized
for You

we will pick new questions that match your level based on your Timer History

Track

every week, we’ll send you an estimated GMAT score based on your performance

Practice
Pays

we will pick new questions that match your level based on your Timer History

## Events & Promotions

###### Events & Promotions in January
PrevNext
SuMoTuWeThFrSa
303112345
6789101112
13141516171819
20212223242526
272829303112
Open Detailed Calendar
• ### Key Strategies to Master GMAT SC

January 26, 2019

January 26, 2019

07:00 AM PST

09:00 AM PST

Attend this webinar to learn how to leverage Meaning and Logic to solve the most challenging Sentence Correction Questions.
• ### Free GMAT Number Properties Webinar

January 27, 2019

January 27, 2019

07:00 AM PST

09:00 AM PST

Attend this webinar to learn a structured approach to solve 700+ Number Properties question in less than 2 minutes.

# During a 7-year period the profits of Midas, Inc. changed by

Author Message
TAGS:

### Hide Tags

Intern
Joined: 18 Feb 2010
Posts: 17
During a 7-year period the profits of Midas, Inc. changed by  [#permalink]

### Show Tags

28 Mar 2010, 00:57
4
1
00:00

Difficulty:

15% (low)

Question Stats:

77% (01:21) correct 23% (01:23) wrong based on 192 sessions

### HideShow timer Statistics

During a 7-year period the profits of Midas, Inc. changed by what percent from the sixth year to the seventh year?

(1) The profits of Midas, Inc. during the seventh year were 50 percent greater than the profits during the third year.
(2) The increase in the profits of Midas, Inc. was the same for each year during the 7-year period.

_________________

If you like my post, shower kudos

Believe that something extraordinary is possible

Manager
Joined: 26 May 2005
Posts: 188

### Show Tags

28 Mar 2010, 04:23
ankithakhu wrote:
During a 7-year period the profits of Midas, Inc. changed by what percent from the sixth year to the seventh year?
(1) The profits of Midas, Inc. during the seventh year were 50 percent greater than the profits during the third year.
(2) The increase in the profits of Midas, Inc. was the same for each year during the 7-year period.

(p7-p6)/p6??
st 1) p7 = p3 * 1.5
Not sufficient
st 2) increase is same for subsequent years.
not sufficient

combining
let increase be a
so p7=p6 + a = p5+2a = p4 + 3a = p3 + 4a = p3*1.5
a = p3/8
but still cannot figure out (p7-p6)/p6

E
Manager
Joined: 01 Feb 2010
Posts: 233

### Show Tags

28 Mar 2010, 06:06
ankithakhu wrote:
During a 7-year period the profits of Midas, Inc. changed by what percent from the sixth year to the seventh year?
(1) The profits of Midas, Inc. during the seventh year were 50 percent greater than the profits during the third year.
(2) The increase in the profits of Midas, Inc. was the same for each year during the 7-year period.

1 & 2 alone are insufficient.
Combining, let x be increase in profit each year.
p7 = p3+4x
p7-p3 = 4x
50 = 4x
x = 12.5%
hence sufficient.
Its C.
Whats the OA.
CEO
Status: Nothing comes easy: neither do I want.
Joined: 12 Oct 2009
Posts: 2591
Location: Malaysia
Concentration: Technology, Entrepreneurship
Schools: ISB '15 (M)
GMAT 1: 670 Q49 V31
GMAT 2: 710 Q50 V35

### Show Tags

28 Mar 2010, 10:32
This increase is the actual increase not increase in %.
_________________

Fight for your dreams :For all those who fear from Verbal- lets give it a fight

Money Saved is the Money Earned

Jo Bole So Nihaal , Sat Shri Akaal

GMAT Club Premium Membership - big benefits and savings

Gmat test review :
http://gmatclub.com/forum/670-to-710-a-long-journey-without-destination-still-happy-141642.html

Intern
Joined: 18 Feb 2010
Posts: 17

### Show Tags

28 Mar 2010, 10:36
1
The OA is C.
Combining the two statements, Let P be the Profit in the third year and x be the increase in profit which is constant. Thus profit in the 6th year = P+3x
and Profit in the 7th year = P+4x
Also from statement 1 Profit in 7th year =1.5 times profit in 3rd year
thus P+4x = 1.5P
thus x=P/8

Hence the percentage increase of 7th year over 6th can now be known.

Hope this is clear.
_________________

If you like my post, shower kudos

Believe that something extraordinary is possible

Manager
Joined: 05 Mar 2010
Posts: 172

### Show Tags

29 Mar 2010, 01:32
Good question Ankit
_________________

Success is my Destiny

Manager
Joined: 10 Aug 2009
Posts: 120

### Show Tags

05 Apr 2010, 08:16
Damn... I was caught in the trap.

Is this a relatively high level question or not?
Intern
Joined: 18 Feb 2010
Posts: 17

### Show Tags

05 Apr 2010, 09:35
No its a simple question. which reinstates the fact that one needs to be really careful, alert and consider all possibilities.
_________________

If you like my post, shower kudos

Believe that something extraordinary is possible

Director
Joined: 27 May 2012
Posts: 671
Re: During a 7-year period the profits of Midas, Inc. changed by  [#permalink]

### Show Tags

25 Aug 2013, 05:33
1
1
ankithakhu wrote:
During a 7-year period the profits of Midas, Inc. changed by what percent from the sixth year to the seventh year?
(1) The profits of Midas, Inc. during the seventh year were 50 percent greater than the profits during the third year.
(2) The increase in the profits of Midas, Inc. was the same for each year during the 7-year period.

This is an interesting old question,But I think needs expert opinion.

we need to know the profits of 6th and 7th year in order to answer this question.

(1) The profits of Midas, Inc. during the seventh year were 50 percent greater than the profits during the third year.
Nothing about the sixth year so Insufficient

(2) The increase in the profits of Midas, Inc. was the same for each year during the 7-year period.

Initially I thought this was sufficient as profits of 6 and 7 year seemed to be same, but that is not so.

The original profits of 6 and 7 year may be different but increase may be same, hence we do not know that actual 6 and 7 year profits.

1+2
from 1
Let 3 year profit be x and 7 year profit is 1.5x still we know nothing about 6 year

from 2 : increase in profits were the same each year , so let the increase in profits be y each year

year ---- profit
3 ------- x
4 ------- x+y
5 ------- x+y+y = x+2y
6 ------- x+3y
7 ------- x+4y

Now we know 6 year profit is x+3y and 7 year profit is x+4y

also we know x+4y=1.5x ( 7 year profit is 1.5 times 3 year profit, we have taken 3 year profit to be x)
on solving x+4y=1.5x we get x= 8y

now 6 year profit is 11y ( from chart above )and 7 year profit is 12y
so profit % increase from 6 to 7 year $$\frac{12y-11y}{11y}*100 =\frac{100}{11} = 9.09$$

We know C is is the answer, but can any one tell me if I have arrived at the correct percentage change in profit?
Thanks
_________________

- Stne

Math Expert
Joined: 02 Sep 2009
Posts: 52431
Re: During a 7-year period the profits of Midas, Inc. changed by  [#permalink]

### Show Tags

25 Aug 2013, 09:28
1
stne wrote:
ankithakhu wrote:
During a 7-year period the profits of Midas, Inc. changed by what percent from the sixth year to the seventh year?
(1) The profits of Midas, Inc. during the seventh year were 50 percent greater than the profits during the third year.
(2) The increase in the profits of Midas, Inc. was the same for each year during the 7-year period.

This is an interesting old question,But I think needs expert opinion.

we need to know the profits of 6th and 7th year in order to answer this question.

(1) The profits of Midas, Inc. during the seventh year were 50 percent greater than the profits during the third year.
Nothing about the sixth year so Insufficient

(2) The increase in the profits of Midas, Inc. was the same for each year during the 7-year period.

Initially I thought this was sufficient as profits of 6 and 7 year seemed to be same, but that is not so.

The original profits of 6 and 7 year may be different but increase may be same, hence we do not know that actual 6 and 7 year profits.

1+2
from 1
Let 3 year profit be x and 7 year profit is 1.5x still we know nothing about 6 year

from 2 : increase in profits were the same each year , so let the increase in profits be y each year

year ---- profit
3 ------- x
4 ------- x+y
5 ------- x+y+y = x+2y
6 ------- x+3y
7 ------- x+4y

Now we know 6 year profit is x+3y and 7 year profit is x+4y

also we know x+4y=1.5x ( 7 year profit is 1.5 times 3 year profit, we have taken 3 year profit to be x)
on solving x+4y=1.5x we get x= 8y

now 6 year profit is 11y ( from chart above )and 7 year profit is 12y
so profit % increase from 6 to 7 year $$\frac{12y-11y}{11y}*100 =\frac{100}{11} = 9.09$$

We know C is is the answer, but can any one tell me if I have arrived at the correct percentage change in profit?
Thanks

Yes, the actual increase is 100/11%.
_________________
Senior Manager
Joined: 08 Dec 2015
Posts: 292
GMAT 1: 600 Q44 V27
Re: During a 7-year period the profits of Midas, Inc. changed by  [#permalink]

### Show Tags

20 Jan 2017, 10:06
mikemcgarry

Hi Mike, I need your help here...

I think that you explain thing really well, so you might help me a lot

I can't understand what is happening here.. How can we add percents?? Aren't we supposed to multiply the starting value by the percent to get the percent change? Why are we summing percents???

Omg I am so lost with this topic and it's so important on the test. Plus I am running out of questions and I just cant seem to grab the fundamentals. I am 100% sure I understand all the basics but I keep getting these Qs wrong all the time.. Please help!
Magoosh GMAT Instructor
Joined: 28 Dec 2011
Posts: 4485
Re: During a 7-year period the profits of Midas, Inc. changed by  [#permalink]

### Show Tags

20 Jan 2017, 14:40
1
iliavko wrote:
mikemcgarry

Hi Mike, I need your help here...

I think that you explain thing really well, so you might help me a lot

I can't understand what is happening here.. How can we add percents?? Aren't we supposed to multiply the starting value by the percent to get the percent change? Why are we summing percents???

Omg I am so lost with this topic and it's so important on the test. Plus I am running out of questions and I just cant seem to grab the fundamentals. I am 100% sure I understand all the basics but I keep getting these Qs wrong all the time.. Please help!

Dear iliavko,

My friend, thank you for your kind words. I am happy to respond.

The first thing I'll say is that when we have a series of percent changes, one after the other---say a 40%, then a 30% increase on that, then a 20% decrease--never think addition. Think multiplication.

In fact, for any percent increase or decrease, you should be thinking about these in terms of multiplication. Read this thoroughly:
Understanding Percents on the GMAT

Thus, to accomplish the proposed series of percent changes above, we would find the multipliers for each and multiply them together (I used a calculator to get the product--that's beyond what the GMAT would expect you compute in your head!)
(1.4)*(1.3)*(0.80) = 1.456
Thus, if we have an initial amount, and we increase by 40%, then increase by 30%, then decrease by 20%, that's equivalent to a 45.6% increase over the initial amount.

Now, if you read the blog thoroughly and understand all that, we can look at this problem:
During a 7-year period the profits of Midas, Inc. changed by what percent from the sixth year to the seventh year?
(1) The profits of Midas, Inc. during the seventh year were 50 percent greater than the profits during the third year.
(2) The increase in the profits of Midas, Inc. was the same for each year during the 7-year period.

The individual statements are not sufficient. Let's deal with the combined statements. Let's say that x is the percent change from year to year, written as a decimal. Thus, x would be the answer to the prompt question, because the change from year 6 to year 7 would be the same as the change from any other year.

The multiplier for a change from one year to the next is (1 + x). Let P3 be profit in the third year, P4, profit in the 4th year, etc. We know

P4 = P3*(1 + x)
P5 = P4*(1 + x) = P3*(1 + x)^2
P6 = P5*(1 + x) = P3*(1 + x)^3
P7 = P6*(1 + x) = P3*(1 + x)^4

Now, since we also know that P7 = 1.5*P3, that allows us to set up an equation:

1.5 = (1 + x)^4

We'd need a calculator to solve for the exact value, but that doesn't matter. This is DS, it's enough to know that we could solve for the exact value of x and answer the prompt question. Both statements together are sufficient. Answer = (C).

BTW, x = .10668192..., about 10.67%

Does all this make sense?
Mike
_________________

Mike McGarry
Magoosh Test Prep

Education is not the filling of a pail, but the lighting of a fire. — William Butler Yeats (1865 – 1939)

Non-Human User
Joined: 09 Sep 2013
Posts: 9465
Re: During a 7-year period the profits of Midas, Inc. changed by  [#permalink]

### Show Tags

05 Aug 2018, 07:40
Hello from the GMAT Club BumpBot!

Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).

Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.
_________________
Re: During a 7-year period the profits of Midas, Inc. changed by &nbs [#permalink] 05 Aug 2018, 07:40
Display posts from previous: Sort by