Does r = 3?

Question

Does r = 3?

(1)  \frac{r}{3} = \frac{(27*27)}{(9*9*9)}

(2)  3r = \frac{(27+27)}{(3+3)}

Gladiator59 · Answer

We need to answer if r = 3? in Yes or No. Either one is a definite ans.

(1) We can find the value of r.  Hence sufficient.   ( On solving r = 3 so answer is "Yes" but we need not find it as a deterministic answer is there without solving as well! )

(2) We can solve for r.  Hence Sufficient!  (  On solving we find that r does not equal 3 and answer is "No" , but again we need to solve to find this. )

Hence Option (D) is the choice.

Best,
Gladi

p.s - This is one example where the two statements both give a deterministic answer to the question and the answer is different for the two statements. But note, either one can be used to come up with the solution and hence D is the answer and not E. ( (1) + (2) together gives two values to r... but since (1) and (2) together are able to give answers we need not check (1) + (2) together. )

vishalkazone · Answer

St:1
r/3 = (27∗27)/(9∗9∗9) = 1
r=3
Sufficient

St:2

3r=(27∗27)/(3+3) 
r= (27*27) /(6*3) = 81/2
answer confirmed NO ( sufficient)
D.
 gmatbusters  How we can get two different value of r from each statement?

GMATBusters · Answer

There was a typo, thanks for pointing out the typo.
the Question has been revised.

bumpbot · Answer

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Does r = 3?

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