The National Gross Product (NGP) of Andalasia had decreased by 25 perc

Question

The National Gross Product (NGP) of Andalasia had decreased by 25 percent. Due to the ongoing war with Actasia, the NGP has decreased by an additional 10 percent. By approximately what percent would the NGP now have to be increased in order to restore it to its original amount?

A. 32.5%
B. 35%
C. 48%
D. 65%
E. 67.5%

A. 32.5%
B. 35%
C. 48%
D. 65%
E. 67.5%

asishron29181 · Answer

Let the original NGP = 100
Decreased by 25%
Hence new NGP = 75
War effect, additional decrease of 10% 
Hence the new NGP = 0.9 * 75 = 67.5%
Hence in order to restore it to original amount it should be increased by = 100 - 67.5 = 32.5 %

IMO A

sumitkrocks · Answer

(C)  is correct IMO

Say NGP is 100 initially

Value after 25% decrease = 100 -25 = 75 
Further decease of 10% = 75 - 0.1*75 = 0.9*75 = 67.5
Overall NGP is reduced by = 100 - 67.5 = 32.5 
So increase required =  \frac{32.5*100}{67.5}  ~48

ostrick5465 · Answer

The original NGP = 100%
Decreased by 25%
NGP = 75% The original NGP
War effect, additional decrease of 10%
=> new NGP = 0.9 * 75 = 67.5%
 in order to restore it to original amount it should be increased by  \frac{(100 - 67.5)}{67.5} * 100%   ~ 48%

Choice C

Archit3110 · Answer

let original be 100
so decrease 25 = 75
then 10% decrease = 75*.9 ; 67.5
need % increase to get 100
67.5*x/100 = 100 ; 148 or say 48%
option C

MV94 · Answer

I like fractions here:

Decrease by 25% = 1 * 3/4
Decrease by 10% more = 1 * 3/4 * 9/10 = 27/40

In order to get back to 1, we need to multiply by the inverse.

40/27 = 1 and 13/27

13/27 is very close to 40%, just a touch below

48% it is.  Answer = C

Bunuel · Answer

This question is a part of  Are You Up For the Challenge: 700 Level Questions  collection.

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The National Gross Product (NGP) of Andalasia had decreased by 25 perc

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