Last visit was: 23 Apr 2026, 18:25 It is currently 23 Apr 2026, 18:25
Close
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
Your Progress

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
Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.
Close
Request Expert Reply
Confirm Cancel
User avatar
MathRevolution
User avatar
Math Revolution GMAT Instructor
Joined: 16 Aug 2015
Last visit: 27 Sep 2022
Posts: 10,063
Own Kudos:
20,000
 [13]
Given Kudos: 4
GMAT 1: 760 Q51 V42
GPA: 3.82
Expert
Expert reply
GMAT 1: 760 Q51 V42
Posts: 10,063
Kudos: 20,000
 [13]
2
Kudos
Add Kudos
11
Bookmarks
Bookmark this Post
Most Helpful Reply
User avatar
MathRevolution
User avatar
Math Revolution GMAT Instructor
Joined: 16 Aug 2015
Last visit: 27 Sep 2022
Posts: 10,063
Own Kudos:
20,000
 [18]
Given Kudos: 4
GMAT 1: 760 Q51 V42
GPA: 3.82
Expert
Expert reply
GMAT 1: 760 Q51 V42
Posts: 10,063
Kudos: 20,000
 [18]
3
Kudos
Add Kudos
15
Bookmarks
Bookmark this Post
avatar
User4316
Joined: 29 Aug 2020
Last visit: 28 Jun 2021
Posts: 2
Own Kudos:
10
 [9]
Given Kudos: 96
Schools: NUS MiF "22
Schools: NUS MiF "22
Posts: 2
Kudos: 10
 [9]
5
Kudos
Add Kudos
4
Bookmarks
Bookmark this Post
General Discussion
User avatar
MathRevolution
User avatar
Math Revolution GMAT Instructor
Joined: 16 Aug 2015
Last visit: 27 Sep 2022
Posts: 10,063
Own Kudos:
20,000
 [2]
Given Kudos: 4
GMAT 1: 760 Q51 V42
GPA: 3.82
Expert
Expert reply
GMAT 1: 760 Q51 V42
Posts: 10,063
Kudos: 20,000
 [2]
Kudos
Add Kudos
2
Bookmarks
Bookmark this Post
(Functions): If 2f (x) + 3f (−x) = 2x − 4, what is the value of 5f (1)?

A) 14/5
B) -2
C) 14
D) -14/5
E) -14
User avatar
MathRevolution
User avatar
Math Revolution GMAT Instructor
Joined: 16 Aug 2015
Last visit: 27 Sep 2022
Posts: 10,063
Own Kudos:
20,000
 [2]
Given Kudos: 4
GMAT 1: 760 Q51 V42
GPA: 3.82
Expert
Expert reply
GMAT 1: 760 Q51 V42
Posts: 10,063
Kudos: 20,000
 [2]
Kudos
Add Kudos
2
Bookmarks
Bookmark this Post
MathRevolution
(Functions): If 2f (x) + 3f (−x) = 2x − 4, what is the value of 5f (1)?

A) 14/5
B) -2
C) 14
D) -14/5
E) -14


Thank you for your replies GMAT Club members. GMAT quant is based on logic, tricks, and quick approaches. Always try to find a quick approach to solve any PS or a DS question. We apply the IVY approach for PS and Variable Approach for DS.


Solution: 2f(x) + 3 f(-x) = 2x - 4 --------- equation (1)

Substituting x = 1 in equation (1)

2f(1) + 3f(-1) = 2(1) – 4 =2 – 4= -2

2f(1) + 3f(-1) = -2--------- equation (2)

Substituting x = -1 in equation (1)

2f(-1) + 3f(1) = 2(-1) – 4 = -2 – 4 = -6

2f(-1) + 3f(1) = -6--------- equation (3)

Multiplying equation (2) by ‘2’ we get,

4f(1) + 6f(-1) = -4--------- equation (4)


Multiplying equation (3) by ‘3’ we get,

9f(1) + 6f(-1) = -18--------- equation (5)

Subtracting Eqn(5) - Eqn(4)

=> 5f(1) = -14

=> f(1) = \(\frac{-14}{5}\)

D is the correct answer.

Answer D
User avatar
MathRevolution
User avatar
Math Revolution GMAT Instructor
Joined: 16 Aug 2015
Last visit: 27 Sep 2022
Posts: 10,063
Own Kudos:
20,000
 [3]
Given Kudos: 4
GMAT 1: 760 Q51 V42
GPA: 3.82
Expert
Expert reply
GMAT 1: 760 Q51 V42
Posts: 10,063
Kudos: 20,000
 [3]
1
Kudos
Add Kudos
2
Bookmarks
Bookmark this Post
MathRevolution
(Integers) If m, n, p, and q are distinct positive integers, greater than 1 such that mnpq = 660 and m<n<p<q, how many possible combinations of values exist for m, n, p, and q?

A) Two
B) Three
C) Four
D) Five
E) Seven

Thank you for your replies GMAT Club members. GMAT quant is based on logic, tricks, and quick approaches. Always try to find a quick approach to solve any PS or a DS question. We apply the IVY approach for PS and Variable Approach for DS.


Solution: Let us find the prime factors of 660.

660 can be written as 660 = 2 * 2 * 3 * 5 * 11.

We have an extra ‘2’ and this can be combined with other factors to generate different values.

Also, considering all other factors than ‘2’, we may combine to generate different values for m, n, p, and q.

Attachment:
Possible Combinations.jpg
Possible Combinations.jpg [ 22.3 KiB | Viewed 14310 times ]

Therefore, we have ‘4’ possible combinations.

C is the correct answer.

Answer C.
User avatar
MathRevolution
User avatar
Math Revolution GMAT Instructor
Joined: 16 Aug 2015
Last visit: 27 Sep 2022
Posts: 10,063
Own Kudos:
20,000
 [1]
Given Kudos: 4
GMAT 1: 760 Q51 V42
GPA: 3.82
Expert
Expert reply
GMAT 1: 760 Q51 V42
Posts: 10,063
Kudos: 20,000
 [1]
1
Kudos
Add Kudos
Bookmarks
Bookmark this Post
(PS)- If the speed limit along a 20-mile section of rail track is reduced from 40 miles per hour to 30 miles per hour. Approximately how many minutes more will it take a rail to travel along this section with the new speed limit than it would have taken at the old speed limit?

A) 3
B) 5
C) 8
D) 10
E) 12
User avatar
MathRevolution
User avatar
Math Revolution GMAT Instructor
Joined: 16 Aug 2015
Last visit: 27 Sep 2022
Posts: 10,063
Own Kudos:
20,000
 [2]
Given Kudos: 4
GMAT 1: 760 Q51 V42
GPA: 3.82
Expert
Expert reply
GMAT 1: 760 Q51 V42
Posts: 10,063
Kudos: 20,000
 [2]
2
Kudos
Add Kudos
Bookmarks
Bookmark this Post
MathRevolution
(PS)- If the speed limit along a 20-mile section of rail track is reduced from 40 miles per hour to 30 miles per hour. Approximately how many minutes more will it take a rail to travel along this section with the new speed limit than it would have taken at the old speed limit?

A) 3
B) 5
C) 8
D) 10
E) 12


Solution: Always apply the IVY approach to solve PS questions accurately thus saving time.

Speed * Time = Distance

Length of the section = 20 miles

Original speed limit: 40 miles per hour

Thus, time is taken to cover this distance = \(\frac{20}{40}= \frac{1}{2}\)

New speed limit: 30 miles per hour

Thus, time is taken to cover this distance = \(\frac{20}{30} = \frac{2}{3}\)

Thus, the required difference between the time durations is given = \(\frac{2}{3} - \frac{1}{2} \) = \(\frac{1}{6}\) hours

=> \(\frac{1}{6} * 60 = 10\) minutes

D is the correct answer.

Answer D.
User avatar
MathRevolution
User avatar
Math Revolution GMAT Instructor
Joined: 16 Aug 2015
Last visit: 27 Sep 2022
Posts: 10,063
Own Kudos:
Given Kudos: 4
GMAT 1: 760 Q51 V42
GPA: 3.82
Expert
Expert reply
GMAT 1: 760 Q51 V42
Posts: 10,063
Kudos: 20,000
Kudos
Add Kudos
Bookmarks
Bookmark this Post
(Statistics) Heights of citizens in a large population have a distribution that is symmetric about the mean m. If 68 percent of the distribution lies within one standard deviation d of the mean, what percent of the distribution is greater than (m − d)?

A) 66%
B) 50%
C) 67%
D) 84%
E) 34%
User avatar
MathRevolution
User avatar
Math Revolution GMAT Instructor
Joined: 16 Aug 2015
Last visit: 27 Sep 2022
Posts: 10,063
Own Kudos:
20,000
 [3]
Given Kudos: 4
GMAT 1: 760 Q51 V42
GPA: 3.82
Expert
Expert reply
GMAT 1: 760 Q51 V42
Posts: 10,063
Kudos: 20,000
 [3]
1
Kudos
Add Kudos
2
Bookmarks
Bookmark this Post
MathRevolution
(Statistics) Heights of citizens in a large population have a distribution that is symmetric about the mean m. If 68 percent of the distribution lies within one standard deviation d of the mean, what percent of the distribution is greater than (m − d)?

A) 66%
B) 50%
C) 67%
D) 84%
E) 34%


Solution: We know that the distribution is symmetric about the mean. This is the concept of Normal distribution.

Thus, the percent of the distribution equidistant from the mean on either side of it is the same.

Let the percent of the distribution less than (m- d) be x%. Thus, the percent of the distribution more than (m+ d) is also x%.

Thus, we have

=> x% + 68% + x% = 100%

=> 2x = 32%, x=16%

Thus, the percent of the distribution greater than (m − d) = 100% - x% =100%-16% = 84%.

D is the correct answer.

Answer D
User avatar
MathRevolution
User avatar
Math Revolution GMAT Instructor
Joined: 16 Aug 2015
Last visit: 27 Sep 2022
Posts: 10,063
Own Kudos:
20,000
 [2]
Given Kudos: 4
GMAT 1: 760 Q51 V42
GPA: 3.82
Expert
Expert reply
GMAT 1: 760 Q51 V42
Posts: 10,063
Kudos: 20,000
 [2]
1
Kudos
Add Kudos
1
Bookmarks
Bookmark this Post
A ball thrown up in the air is at a height of h feet, t seconds after it was thrown, where \(h = −3(t − 10)^2 + 250\). What is the height of the ball once it reached its maximum height and then descended for 7 seconds

A) 96 feet
B) 103 feet
C) 164 feet
D) 223 feet
E) 250 feet

Solution: We know that \(h = −3(t − 10)^2 + 250\)

We will first find the value for ‘t’ for which ‘h’ will be maximum.

For ‘h’ to be maximum, \(−3(t − 10)^2\) should be maximum. Since \((t − 10)^2\) is a perfect square, therefore, \((t − 10)^2\) ≥ 0.

But, \(−3(t − 10)^2\) will be ≤ 0 [By the property of reverse inequality]

So, for ‘h’ to be maximum \(−3(t − 10)^2\)= 0

=> \(−3(t − 10)^2\) = 0

=> \((t − 10)^2\) = 0

=> (t − 10) = 0

=> t = 10.

‘7’ seconds after ball has reached maximum height ‘h’ at t = 10 + 7 = 17.

=> \(h = −3(t − 10)^2 + 250\)

=> \(h = −3(17 − 10)^2 + 250\)

=> h = −3 * 49 + 250

=> h = -147 + 250

=> h = 103 feet

Answer B
avatar
jlee818
Joined: 10 Oct 2020
Last visit: 18 Aug 2021
Posts: 2
Own Kudos:
3
 [3]
Given Kudos: 1
Posts: 2
Kudos: 3
 [3]
2
Kudos
Add Kudos
1
Bookmarks
Bookmark this Post
Hey, got this problem on one of my practice tests and cannot figure it out or understand the explanation given... Can someone break this down? Cheers and happy studying

† and ¥ represent nonzero digits, and (†¥)² - (¥†)² is a perfect square. What is that perfect square?

(a) 121
(b) 361
(c) 576
(d) 961
(e) 1089
avatar
ahn910325
Joined: 17 Nov 2018
Last visit: 09 Dec 2020
Posts: 1
Posts: 1
Kudos: 0
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Hi, this question looks easy but so difficult for me. Please help to solve this one, thank you :)
-----
Raymond purchased a package of ground beef at a cost of $1.98 per pound. If, for the same amount of money, Raymond could have purchased a piece of steak that weighed 40 percent less than the package of ground beef, what was the cost per pound of the steak?

A 4.95, B 4.20, C 3.6, D 3.3, E 3.10
User avatar
Bunuel
User avatar
Math Expert
Joined: 02 Sep 2009
Last visit: 23 Apr 2026
Posts: 109,785
Own Kudos:
Given Kudos: 105,853
Products:
Expert
Expert reply
Active GMAT Club Expert! Tag them with @ followed by their username for a faster response.
Posts: 109,785
Kudos: 810,873
Kudos
Add Kudos
Bookmarks
Bookmark this Post
ahn910325
Hi, this question looks easy but so difficult for me. Please help to solve this one, thank you :)
-----
Raymond purchased a package of ground beef at a cost of $1.98 per pound. If, for the same amount of money, Raymond could have purchased a piece of steak that weighed 40 percent less than the package of ground beef, what was the cost per pound of the steak?

A 4.95, B 4.20, C 3.6, D 3.3, E 3.10

This question is discussed here: https://gmatclub.com/forum/raymond-purc ... 07469.html Hope it helps.

P.S. Please read carefully our posting rules: https://gmatclub.com/forum/rules-for-po ... 33935.html Thank you,
User avatar
Rbn
Joined: 10 Jul 2020
Last visit: 19 Feb 2024
Posts: 5
Own Kudos:
6
 [2]
Given Kudos: 229
Posts: 5
Kudos: 6
 [2]
2
Kudos
Add Kudos
Bookmarks
Bookmark this Post
jlee818
Hey, got this problem on one of my practice tests and cannot figure it out or understand the explanation given... Can someone break this down? Cheers and happy studying

† and ¥ represent nonzero digits, and (†¥)² - (¥†)² is a perfect square. What is that perfect square?

(a) 121
(b) 361
(c) 576
(d) 961
(e) 1089

I broke the question into:
(10† + ¥)² - (10¥ + †)²
opening up the brackets gives
(100†² + 20†¥ + ¥²) - (100¥² + 20†¥ - †²)
Simplifying further gives
100{†²- ¥²} + {¥² - †²}
factoring the second bracket with -1
100{†²- ¥²} - {†²-¥²}
{†²- ¥²}(100 -1)
{†²- ¥²} 99
Hence the number must be a multiple of 99.

In the Answer options 1089 divides 99 to give 11.
Answer E is the correct choice.

(Kindly check if there are any errors in there)

Posted from my mobile device
User avatar
MathRevolution
User avatar
Math Revolution GMAT Instructor
Joined: 16 Aug 2015
Last visit: 27 Sep 2022
Posts: 10,063
Own Kudos:
Given Kudos: 4
GMAT 1: 760 Q51 V42
GPA: 3.82
Expert
Expert reply
GMAT 1: 760 Q51 V42
Posts: 10,063
Kudos: 20,000
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Que: A fitness club has 40 male and 10 female members. The average (arithmetic mean) age of all of the members is 24 years. If the average age of the male members was 22 years, which of the following is the average age, in years, of the female members?

(A) 25
(B) 30
(C) 32
(D) 34
(E) 26
User avatar
MathRevolution
User avatar
Math Revolution GMAT Instructor
Joined: 16 Aug 2015
Last visit: 27 Sep 2022
Posts: 10,063
Own Kudos:
Given Kudos: 4
GMAT 1: 760 Q51 V42
GPA: 3.82
Expert
Expert reply
GMAT 1: 760 Q51 V42
Posts: 10,063
Kudos: 20,000
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Que: A number 4p25q is divisible by 4 and 9; where p and q are the thousands and units digits, respectively. What is the minimum value of \(\frac{p}{ q}\)

(A) \(\frac{1}{8}\)
(B) \(\frac{1}{7}\)
(C) \(\frac{1}{6}\)
(D) \(\frac{2}{5}\)
(E) \(\frac{5}{2}\)
User avatar
MathRevolution
User avatar
Math Revolution GMAT Instructor
Joined: 16 Aug 2015
Last visit: 27 Sep 2022
Posts: 10,063
Own Kudos:
Given Kudos: 4
GMAT 1: 760 Q51 V42
GPA: 3.82
Expert
Expert reply
GMAT 1: 760 Q51 V42
Posts: 10,063
Kudos: 20,000
Kudos
Add Kudos
Bookmarks
Bookmark this Post
MathRevolution
Que: A fitness club has 40 male and 10 female members. The average (arithmetic mean) age of all of the members is 24 years. If the average age of the male members was 22 years, which of the following is the average age, in years, of the female members?

(A) 25
(B) 30
(C) 32
(D) 34
(E) 26

Solution: We have 40 males and 10 females. Hence, total members are: 40 + 10 = 50

Let the average age, in years, of the female members be x, then we get

=> \(\frac{(40 * 22 + 10 * x)}{(40+10)}\)=24

=> 40 * 22 + 10x = 24 * 50

=> 880 + 10x = 1,200

10x=1200 – 880 = 320 which means that the sum of the ages of 10 female members is 320

Also, we get 10x = 320, x = \(\frac{320}{10}\) = 32, which means that the average age of these 10 female members is = 32.

C is the correct answer.

Answer C
User avatar
MathRevolution
User avatar
Math Revolution GMAT Instructor
Joined: 16 Aug 2015
Last visit: 27 Sep 2022
Posts: 10,063
Own Kudos:
20,000
 [1]
Given Kudos: 4
GMAT 1: 760 Q51 V42
GPA: 3.82
Expert
Expert reply
GMAT 1: 760 Q51 V42
Posts: 10,063
Kudos: 20,000
 [1]
1
Kudos
Add Kudos
Bookmarks
Bookmark this Post
MathRevolution
Que: A number 4p25q is divisible by 4 and 9; where p and q are the thousands and units digits, respectively. What is the minimum value of \(\frac{p}{ q}\)

(A) \(\frac{1}{8}\)
(B) \(\frac{1}{7}\)
(C) \(\frac{1}{6}\)
(D) \(\frac{2}{5}\)
(E) \(\frac{5}{2}\)

Solution: Divisibility property of ‘4’: A number is divisible by ‘4’ when its last two digits are divisible by ‘4’.

Therefore, ‘5q’ is divisible by 4.

So, the possible values of ‘q’ are 2 or 6 [both 52 and 56 are divisible by 4]

Divisibility property of ‘9’: A number is divisible by ‘9’ when the sum of all its digits is divisible by ‘9’

Therefore, 4 + p + 2 + 5 + q = 11 + p + q.

So, the possible values of ‘p’ and ‘q’ so that 11 + p + q is divisible by ‘9’are:

For q = 2

=> 11 + p + 2 = 13 + p

=>‘p’ should be 5 [since 13 + 5 = 18 is divisible by 9]

For q = 6

=> 11 + p + 6 = 17 + p
=> ‘p’ should be 1 [since 17 + 1 = 18 is divisible by 9]

So, we have two pairs for ‘p’ and ‘q’: (5, 2) and (1,6)

=> Minimum value of \(\frac{p}{q}\) = \(\frac{1}{6}\)

C is the correct answer.

Answer C
User avatar
MathRevolution
User avatar
Math Revolution GMAT Instructor
Joined: 16 Aug 2015
Last visit: 27 Sep 2022
Posts: 10,063
Own Kudos:
Given Kudos: 4
GMAT 1: 760 Q51 V42
GPA: 3.82
Expert
Expert reply
GMAT 1: 760 Q51 V42
Posts: 10,063
Kudos: 20,000
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Que: A chemical evaporates out of a beaker at the rate of x liters for every y minutes. If the chemical costs 25 dollars per liter, what is the cost, in dollars, of the amount of the chemical that will evaporate in z minutes?

(A) \(\frac{25}{yz}\)

(B) \(\frac{xz}{25q}\)

(C) \(\frac{25y}{xz}\)

(D) \(\frac{25xz}{y}\)

(E) \(\frac{25yz}{x}\)
 1   2   3   4   5   6   7   8   9   10   
Moderator:
Math Expert
109785 posts