daughter sarah was born

This topic has expert replies
Source: — Problem Solving |

User avatar
Legendary Member
Posts: 871
Joined: Wed Aug 13, 2008 7:48 am
Thanked: 48 times

by stop@800 » Thu Oct 09, 2008 11:41 pm
at birth 24, 0

[for equation using x and you will easily get the answer]

Now 36, 12

4 times at
(32, 8)

so 4 years ago

Hope this helps!!

Senior | Next Rank: 100 Posts
Posts: 66
Joined: Sat Sep 29, 2007 7:17 pm
Thanked: 5 times
GMAT Score:660

by ssy » Thu Oct 09, 2008 11:44 pm
Is the answer 4?

I did this by picking numbers. As Aaron is now 3 times the age of Sarah, you know that the numerical value of his age must be a multiple of three. So, only pick numbers which is a multiple of three from 24 onwards.

So Aaron = 27yrs and Sarah = 27-24 = 3 yrs (NO) / Aaron = 30 years and Sarah = 6 years (NO) / Aaron = 33 years and Sarah = 9 year (NO), Aaron = 36 years and Sarah = 12 years (YES!)

12 x 3 = 36, so Aaron is now 36 while Sarah is 12.

To find out how many years ago it's been since Aaron was 4 times Sarah's age, I just plugged in the answer choices.

8 years ago, Aaron was 28 while Sarah was 4. 4x4 does not equal 28.

4 years Ago, Aaron was 32 while Sarah was 8. 8x4 equals 28.

Hence the answer is 4.

Legendary Member
Posts: 1159
Joined: Wed Apr 16, 2008 10:35 pm
Thanked: 56 times

by raunekk » Fri Oct 10, 2008 3:07 am
ans:4


A=24
s=0 wen born

now,let x yrs be passed

thus, A+x=3(s+x)
i,e 24+x=3(0+x)
thus x=12

thus ,now
A=24+12=36
S=12
now,y yrs back
36-y=4(12-y)

solving
we get y =4


Thus ans:4