If s and t are positive integers and s/t = 39.12, then which one of th

Question

If s and t are positive integers and s/t = 39.12, then which one of the following could t equal?

(A) 8
(B) 13
(C) 15
(D) 60
(E) 75

BrentGMATPrepNow · Accepted Answer

First take 39.12 and convert into a FRACTION to get 3912/100
In other words, s/ t  = 3912/ 100

So, as you can see,  t  COULD equal  100  (this is why the question asks, "Which of the following COULD t equal?")
Since  100  isn't one of the answer choices, we'll keep going

Simplify the fraction to get: 978/ 25 
Since  25  isn't one of the answer choices, we'll keep going
 
At this point we can see that, if we take 978/ 25  and multiply numerator and denominator by 3, we get the equivalent fraction 2934/ 75 
So, t COULD equal  75

Answer: E

Cheers,
Brent

kunalcvrce · Answer

s/t=3912/100=978/25=978*3/25*3=X/75

Option E

Flixus16 · Answer

Could you please explain following step: 978*3/25*3=X/75

I don't understand why you multiplied everything by 3.

Thanks

lucajava · Answer

Flixus16  he multiplied the fraction set forth above by 3 to get 75 as multiple of 25. The reasoning behind is that you need 25 or a multiple of it. Hence, 25*3= 75.

EgmatQuantExpert · Answer

Solution

Given  
 • s and t are positive integers
• s/t = 39.12

To find  
 • Find one of the possible value of t

Approach and Working out

• s=39 t + 0.12 t
• S and t are integer.
 o So, 0.12 t must also be an integer.
o 0.12 t= 12/100 t = 3/25t
o For 3/25 t to be an integer, t must be divisible by 25.

Hence, option E is the correct answer.

Correct Answer: Option E

ScottTargetTestPrep · Answer

We can create the equation:

s/t = 39 + 12/100

s/t = 39 + 3/25

Since s/t = Q + r/t, we see that t must be a multiple of 25, so t could be 75.

Answer: E

rito54 · Answer

Hello, yes could we explain here, does it mean that we need to find something that is the multiple of both the numerator and denominator in that case? 
thank you very much for you valuable help  Bunuel

Bunuel · Answer

Not sure I follow your question, but here's a solution.

If s and t are positive integers and s/t = 39.12, then which one of the following could t equal?

(A) 8
(B) 13
(C) 15
(D) 60
(E) 75

\frac{s}{t} = 39.12 =

=39\frac{12}{100} =

=\frac{39*100 + 12}{100} =

=\frac{3912}{100} =

=\frac{978}{25}

The above implies that t must be a multiple of 25.

The only answer that fits is E.

unraveled · Answer

If s and t are positive integers and s/t = 39.12, then which one of the following could t equal?

(A) 8
(B) 13
(C) 15
(D) 60
(E) 75
s/t = 39.12 = 3912/100 = 1956/50 = 978/25

Least value possible for t is 25 since 5 is not a factor of 978.
Hence eliminated options are A, B and C.
Now D is not possible since it not a multiple of 25.

Therefore 75 is answer.

Answer E.

bumpbot · Answer

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If s and t are positive integers and s/t = 39.12, then which one of th

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If s and t are positive integers and s/t = 39.12, then which one of th

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