Adam is 40 years old.
Bryan is 4 years old.
In a few years' time, Adam will be 4 times as old as Bryan.
- In how many years' time will Adam be 4 times as old as Bryan?
- How old will Adam be by that time?
|
Adam |
Bryan |
Difference |
Before |
40 |
4 |
36 |
Change |
+ ? |
+ ? |
|
After |
4 u |
1 u |
3 u |
(a)
For Adam to be 4 times as old as Bryan,
Bryan's age = 1 u
Adam's age = 4 u
Difference in their age
= 4 u - 1 u
= 3 u
Age difference between Adam and Bryan
= 40 - 4
= 36
3 u = 36
1 u = 36 ÷ 3 = 12
Number of years' time when Adam will be 4 times as old as Bryan
= 12 - 4
= 8
(b)
Adam's age in 8 years' time
= 4 u
= 4 x 12
= 48
Answer(s): (a) 8; (b) 48