What is the lowest possible number?? :s

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What is the lowest possible number?? :s

by gmatpup » Mon Nov 21, 2011 4:30 am

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A gym class can be divided into 8 teams with an equal number of players on each team or into 12 teams with an equal number of players on each team. What is the lowest possible number of students in the class?

A. 20

B. 24

C. 36

D. 48

E. 96


Answer is B

Thanks again :)

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by Anurag@Gurome » Mon Nov 21, 2011 4:40 am
gmatpup wrote:A gym class can be divided into 8 teams with an equal number of players on each team or into 12 teams with an equal number of players on each team. What is the lowest possible number of students in the class?

A. 20

B. 24

C. 36

D. 48

E. 96


Answer is B

Thanks again :)
The lowest possible number of students in the class = LCM of 8 and 12
8 = 2^3
12 = 2² * 3
So, their LCM = 2^3 * 3 = 8 * 3 = 24

The correct answer is B.
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by Jeff@TargetTestPrep » Thu Apr 09, 2015 12:22 pm
gmatpup wrote:A gym class can be divided into 8 teams with an equal number of players on each team or into 12 teams with an equal number of players on each team. What is the lowest possible number of students in the class?

A. 20

B. 24

C. 36

D. 48

E. 96


Answer is B

Thanks again :)
Solution:

We are given that a gym class can be divided into 8 teams or 12 teams, with an equal number of players on each team. Translating this into two mathematical expressions we can say, where G is the total number of students in the gym class, that:

G/8 = integer and G/12 = integer

This means that G is a multiple of both 8 and 12.

We are asked to determine the lowest number of students in the class, or the lowest value for variable "G". Because we know that G is a multiple of 8 and of 12, we need to find the least common multiple of 8 and 12. Although there are technical ways for determining the least common multiple, the easiest method is to analyze the multiples of 8 and 12 until we find one in common.

Starting with 8, we have: 8, 16, 24, 32

For 12, we have: 12, 24

For the multiples of 12, we stopped at 24, because we see that 24 is also a multiple of 8. Thus, 24 is the least common multiple of 8 and 12, and therefore we know that the lowest possible number of students in the gym class is 24.

The answer is B

Jeffrey Miller
Head of GMAT Instruction
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by [email protected] » Fri Apr 10, 2015 9:48 am
Hi All,

While this is an old series of posts, and the question itself is not too difficult, there is an important lesson here about how GMAT questions can often be approached in a number of different ways. Here, since the question essentially asks for the least common multiple of both 8 and 12, traditional math can be used to calculate the answer to the question.

The answer choices ARE numbers though, so you can use them to your advantage and TEST THE ANSWERS.

So, which number is the smallest multiple of both 8 and 12? Let's start with Answer A....

Is 20 a multiple of 8?
No, so this cannot be the answer.

Is 24 a multiple of 8?
Yes
Is 24 a multiple of 12?
Yes
Then we're done. THIS is the answer.

Final Answer: B

Be on the lookout for the opportunities that the question writers leave for you. Knowing how to get to the correct answer is great; knowing how to get to the correct answer in the fastest/easiest fashion is better.

GMAT assassins aren't born, they're made,
Rich
Contact Rich at [email protected]
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