If the numerator of a fraction is tripled, and the denominator of a fr

Question

If the numerator of a fraction is tripled, and the denominator of a fraction is doubled, the resulting fraction will reflect an increase of what percent?

A. 16 1⁄6%
B. 25%
C. 33 1⁄3%
D. 50%
E. 66 2⁄3%

ND2SPD · Answer

Using substitution....

4/2 = 2

tripling numerator and doubling denominator we get 12/4 =3

Percent increase = (3-2)/2 = 0.5 = 50%

Ans D

EMPOWERgmatRichC · Answer

Hi All,

This question can be dealt with conceptually or by TESTing VALUES.

We're told that the numerator of a fraction is tripled and the denominator of that same fraction is doubled. We're asked for the resulting increase, in percentage terms, of that fraction.

Let's TEST 2/1

If we triple the numerator and double the denominator, we end up with....

(2x3)/(1x2) = 6/2 = 3

Since we're increasing 2 to 3, we're increasing that fraction by (3-2)/2 = 1/2 of itself = 50%

Final Answer:  D

GMAT assassins aren't born, they're made,
Rich

GMATinsight · Answer

fraction = x / y

New Fraction = 3x / 2y = 1.5(x/y)

i.e. Increase =  *100/(x/y) = 50%

Answer: option D

TeamGMATIFY · Answer

There can be two methods to solve this problem:

1. Plain old method of assuming the variables.
Assume original fraction =  \frac{x}{y} 
Fraction after changes =  \frac{3x}{2y}

%age increase = (new - old)/old * 100 = (3x/2y - x/y ) / (x/y)* 100 =(x/2y) / (x/y)*100 = 1/2*100
= 50 % (Option D)

JeffTargetTestPrep · Answer

We can let the numerator = n and the denominator = d, and we have n/d.
 
Since the numerator of a fraction is tripled and the denominator of a fraction is doubled, we have:
 
3n/2d
 
Let’s determine the percentage increase:
 
(3n/2d - n/d)/n/d x 100
 
(3n/2d - 2n/2d)/n/d x 100
 
(n/2d)/n/d x 100
 
dn/2dn x 100 = 1/2 x 100 = 50%
 
Answer: D

nks2611 · Answer

here we need to understand the stem clearly as the only case when the increase could happen when numerator is > denominator 
take 3/2 now triple 3 and double 2 = 9/4

we can easily calculate the % increase = 9-6/4= 100/2= 50%

hence D

arvind910619 · Answer

IMO D 50%
initial ratio x/y
after changes 3x/2y or 1.5xy that means increase of 50 percent .

bumpbot · Answer

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If the numerator of a fraction is tripled, and the denominator of a fr

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