GMAT PS
Alice’s take home pay was the same for each month last year, and she saved the same fraction of money each month. At the end of the year, the total amount of money saved was 3 times that of his monthly take home pay that she did not save. What fraction of her take home pay did she save last year?
A. ½
B. 1/3
C. 1/4
D. 1/5
E. 1/6
OA: D
I am getting answer C. My approach:
Monthly Spent: x
Annual saving= 3x
Monthly saving=x/4
Please point out flaw in my understanding
I guess calculating annual saving and equation are 2 places where your are making mistake.
Let monthly Salary : x
monthly savings : a*x ( a is the fraction of salary saved.)
equation given
12ax = 3(x-ax)
if we solve this we have
15 ax=3 x
% by 15x on both side we have: a=1/5
Option D
🙂
12ax = yearly saving = 3*monthly amount that is not saved :
monthly amount that is not saved = (Monthly salary) -(Monthly savings) = x-ax
so equation becomes
12ax = 3(x-ax)
Hi Nitesh,
I think you made a mistake by considering the amount saved and amount spent as same.
Clear explanation Priyanshu 🙂
Let’s take here, the monthly income as “x”, Let say “y” is the amount she saves monthly.
then the amount spent monthly is “x-y”
given,
12y = 3(x-y)
Solving it we get,
15y = 3x
we need to find what is y/x ?
which is here, 1/5.
So the answer is D.
Hope this helps 🙂
Thanks aditya for the awesome explanation. It was a easy one!