If v

Question

If v < z, which of the following could be the value of S where 10v/(v + z) + 20z/(v + z) = S and v and z are positive integers?

(A) 25
 (B) 20
 (C) 18
 (D) 14
 (E) 8

Posted from my mobile device

tapariasonal003 · Answer

It is an average question.

10v/v+z + 20z/v+z = S
10v+20z = S(v+z)
Now, This is a average equation
Average of 10 & 20 is 15.. Whichever's variable is greater ( v or z ), the value will move towards that i.e 10 or 20.

Since, v is smaller, The value of average 'S' should be between 10 & 15 - that is 14

So, the answer is 14

Bunuel · Answer

This is a copy of the following GMAT Prep question: https://gmatclub.com/forum/if-x-y-and-k ... 28231.html

Kinshook · Answer

Asked: If v < z, which of the following could be the value of S where 10v/(v + z) + 20z/(v + z) = S and v and z are positive integers?

10v/(v + z) + 20z/(v + z) = S
(10v+20z)/(v+z) = S
10(v+2z)/(v+z) = S

10 (2- v/v+z) = S
10 (1 + z/v+z) = S

S is greater than 10 and less than 20.
Since v<z, S is closer to 20 than 10.

IMO C

AlexTheTrainer · Answer

Replying to Bunuel’s correct reply,

This is indeed an OG question that I rewrote for my own curriculum. Haven’t seen the question in official material for several years, but it’s a fantastic question.

I don’t have the inherent math aptitude to solve the question algebraically. But I’m smart and know stuff - like how GMAT Quant is not traditional math.

I know when the GMAT asks a bizarre question like this and when positive integers are involved, I can pick some basic numbers just to figure out what’s going on.

I always try to pick small numbers, larger numbers, numbers close together, and numbers farther apart.

Since this question has already been posted along with multiple explanations:

Try v = 1, z = 2 (small numbers and close together)

Then try v = 1, z = 100 (Numbers farther apart).

With a fairly high-level of confidence should you be able to select the correct answer.

Posted from my mobile device

bumpbot · Answer

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If v < z, which of the following could be the value of S where 10v/(v

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