If C = 5r/(2s) and s ≠ 0, what is the value of C?

Question

(1) r = 4s
(2) r = 2/5

msk0657 · Answer

Stat 1: r = 4s. Sub this in C = 5r/(2s) => 5(4s)/2s = 10....Sufficient.

Stat 2: C = 5(2)/(2s)(5) => 1/s.. we are not sure about s value..Insufficient..

IMO option A is correct answer

OA please..will correct if I missed anything..

BrentGMATPrepNow · Answer

Target question :    What is the value of C?

Given : C = 5r/(2s) and s ≠ 0

Statement 1 : r = 4s   
Given: C = 5r/(2s) 
Replace r with  4s  to get: C = 5( 4s )/(2s) = 20s/2s = 10
So,  C = 10  
Since we can answer the  target question  with certainty, statement 1 is SUFFICIENT

Statement 2 : r = 2/5  
Given: C = 5r/(2s) 
Replace r with  2/5  to get: C = 5( 2/5 )/(2s) = 2/(2s) = 1/s
As we can see, even with the extra information (r = 2/5), the value of C still depends on the value of s 
As such,  we can't determine the value of C 
Since we cannot answer the  target question  with certainty, statement 2 is NOT SUFFICIENT

Answer =  A

Cheers,
Brent

paidlukkha · Answer

C=5R/2S

S1 R=4S
4S/2S=2
so 5*2 = 10 
Suff

S2
R=2/5
so (5*2/5)/1/2S
(5*2/5)*2S
4S
depending on the value of S, Cs value will change 
NS

A

aniketm.87@gmail.com · Answer

If C = 5r/(2s) and s ≠ 0, what is the value of C?

(1) r = 4s
(2) r = 2/5

A) C = 5*4s/2s = 10 -------> suff

B) C = 5*2/5 / 2s = 1/s -------> insuff

Ans is A) ------> its too easy, am i getting this wrong?

Nasahtahir · Answer

We know s= 0 why are we not using it to cancel out the denominator as anything multiplied with 0 is zero ie undefined?

Bunuel · Answer

The stem says that s does NOT equal to 0: s ≠ 0.

prashantrchawla · Answer

Given C = 5r/(2s) and s ≠ 0, 
Option 1: r = 4s, C= 54s/2s = 20/2 = 10, Sufficient
Option 2: r = 2/5, C = 5*2/5*2s = 1/s, Not sufficient.

Option 1 is sufficient to given the value of C, Answer is A.

bumpbot · Answer

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If C = 5r/(2s) and s ≠ 0, what is the value of C?

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If C = 5r/(2s) and s ≠ 0, what is the value of C?

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