Alicia's take home pay

[divya]

Alicia's take home pay last year was the same each month, and she saved the same fraction of her take-home pay each month. The total amt of money that she saved at the end of the year was 3 times the amt of that portion of her monthly take-home pay that she did not save. If all the money that she saved was from her take-home pay, what fraction of her take-home pay did she save each month?

Answer: 1/5

I started with assuming her take home pay to be y per month
Fraction she saves: x

thus:

12x = 3*12 ( y - x)
12x = 36y -36x
48x = 36y
x/y = 36/48 = 3/4

Not sure what I am doing wrong here !!

[Raj]

Hi Divya,

you shouldn't have to consider the months here since everything is in terms of ratios:

T = total pay
S = total savings

S = 3(T-S)

S/T = 3/4
-Raj.

Alicia's take home pay last year was the same each month, and she saved the same fraction of her take-home pay each month. The total amt of money that she saved at the end of the year was 3 times the amt of that portion of her monthly take-home pay that she did not save. If all the money that she saved was from her take-home pay, what fraction of her take-home pay did she save each month?

Answer: 1/5

I started with assuming her take home pay to be y per month
Fraction she saves: x

thus:

12x = 3*12 ( y - x)
12x = 36y -36x
48x = 36y
x/y = 36/48 = 3/4

Not sure what I am doing wrong here !!

[divya]

thanks Raj.. but the correct answer is 1/5.. I was quite so baffled !!

[Raj]

The wording on this does suck...

S = 3 (T-S)/12 since it is said that the total saving is equal to 3 times that is not saved each month.

S = (T-S)/4

5S = T, hence S/T = 1/5
-Raj.

thanks Raj.. but the correct answer is 1/5.. I was quite so baffled !!

[Guest]

thanks Raj. Good luck on your test next week.

[RonPurewal]

http://www.manhattangmat.com/forums/post10795.html