gmat prep Q

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gmat prep Q

by navalpike » Thu Aug 06, 2009 12:35 pm
Is the average (arithmetic mean) of 5 different positive integers at least 30?

1. Each of the integers is a multiple of 10

2. The sum of the five integers is 160

Please show your process.
Thanks,

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Re: gmat prep Q

by shahdevine » Thu Aug 06, 2009 12:56 pm
navalpike wrote:Is the average (arithmetic mean) of 5 different positive integers at least 30?

1. Each of the integers is a multiple of 10

2. The sum of the five integers is 160

Please show your process.
Thanks,

restate question:

is the sum of the 5 different positive integers at least 150?

statement 1)

each of integers is multiple of 10...so smallest of terms would be 10,20,30,40,50. Sum of the 5 different positive integers is at 150. so it satisfies the question we restated. sufficient

statement 2)

Sum of 5 integers is 160. which satisfies the sum we at least need of 150 to satisfy question. sufficient

D

you got this!

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by saintlychik » Sun Dec 11, 2011 2:36 am
guys could it not have been possible that the 1st multiple of 10 could have been 0 followed by 10, 20, 30, 40.

hence in that case the total would have been 100. and the average 20.

pls help with the question as this one has bothered me time and again.

S

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by shekhar.kataria » Sun Dec 11, 2011 2:44 am
0 is a multiple of 10 and statement 1 would not satisfy the equation where as statement 2 does. Therefore answer would be B.

Original answer please.
saintlychik wrote:guys could it not have been possible that the 1st multiple of 10 could have been 0 followed by 10, 20, 30, 40.

hence in that case the total would have been 100. and the average 20.

pls help with the question as this one has bothered me time and again.

S
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by saintlychik » Sun Dec 11, 2011 2:47 am
OA is D.

apparently the question stem states that there are 5 different POSITIVE MULTIPLES of 10. so we cannot consider 0.

Read it in another forum.

S

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by Anurag@Gurome » Sun Dec 11, 2011 8:41 pm
navalpike wrote:Is the average (arithmetic mean) of 5 different positive integers at least 30?

1. Each of the integers is a multiple of 10

2. The sum of the five integers is 160

Please show your process.
Thanks,

(1) Each of the integers is a multiple of 10.
Let us start from the least multiple of 10. So, if we consider the 5 integers as 10, 20, 30, 40, and 50, then the average of these 5 integers is 30. Now, if we replace the above list by any other list, which will definitely have it's average as more than 30. So, statement 1 is SUFFICIENT.

(2) The sum of the five integers is 160 implies its average will be 160/5 = 32, which is greater than 30; SUFFICIENT.

The correct answer is D.
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by shekhar.kataria » Sun Dec 11, 2011 10:37 pm
My mistake , i just overlooked it. Yeah the answer should be D now
saintlychik wrote:OA is D.

apparently the question stem states that there are 5 different POSITIVE MULTIPLES of 10. so we cannot consider 0.

Read it in another forum.

S
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by amyhussein » Mon Dec 16, 2013 7:49 am
HELLO
WHY WE SHOULD NOT INCLUDE THE -VE MULTIPLES OF 10? THIS WILL NOT MAKE THE AVERAGE STATEMENT SUFFICIENT