Bryan is 40 years old.
Adam is 13 years old.
A few years ago, Bryan was 4 times as old as Adam.
- How many years ago was Bryan 4 times as old as Adam?
- How old was Bryan then?
|
Bryan |
Adam |
Difference |
Before |
4 u |
1 u |
3 u |
Change |
+ ? |
+ ? |
|
After |
40 |
13 |
27 |
(a)
For Bryan to be 4 times as old as Adam,
Adam's age = 1 u
Bryan's age = 4 u
Difference in their age
= 4 u - 1 u
= 3 u
Age difference between Bryan and Adam
= 40 - 13
= 27
3 u = 27
1 u = 27 ÷ 3 = 9
Number of years' ago that Bryan was 4 times as old as Adam
= 13 - 9
= 4
(b)
Bryan's age 4 years ago
= 4 u
= 4 x 9
= 36
Answer(s): (a) 4; (b) 36