Adam is 21 years old.
Bryan is 5 years old.
In a few years' time, Adam will be 3 times as old as Bryan.
- In how many years' time will Adam be 3 times as old as Bryan?
- How old will Adam be by that time?
|
Adam |
Bryan |
Difference |
Before |
21 |
5 |
16 |
Change |
+ ? |
+ ? |
|
After |
3 u |
1 u |
2 u |
(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
= 21 - 5
= 16
2 u = 16
1 u = 16 ÷ 2 = 8
Number of years' time when Adam will be 3 times as old as Bryan
= 8 - 5
= 3
(b)
Adam's age in 3 years' time
= 3 u
= 3 x 8
= 24
Answer(s): (a) 3; (b) 24