Adam is 39 years old.
Bryan is 23 years old.
A few years ago, Adam was 3 times as old as Bryan.
- How many years ago was Adam 3 times as old as Bryan?
- How old was Adam then?
|
Adam |
Bryan |
Difference |
Before |
3 u |
1 u |
2 u |
Change |
+ ? |
+ ? |
|
After |
39 |
23 |
16 |
(a)
For Adam to be 3 times as old as Bryan,
Bryan's age = 1 u
Adam's age = 3 u
Difference in their age
= 3 u - 1 u
= 2 u
Age difference between Adam and Bryan
= 39 - 23
= 16
2 u = 16
1 u = 16 ÷ 2 = 8
Number of years' ago that Adam was 3 times as old as Bryan
= 23 - 8
= 15
(b)
Adam's age 15 years ago
= 3 u
= 3 x 8
= 24
Answer(s): (a) 15; (b) 24