Bryan was 5 times as old as Adam 20 years ago.
Their total present age is 70 years now.
- How old is Bryan now?
- How many years is Bryan older than Adam?
- How old is Adam in 25 years' time?
| |
Bryan |
Adam |
Total |
| 20 years ago |
5 u |
1 u |
6 u |
| Change |
+ 20 |
+ 20 |
+ 40 |
| Present |
5 u + 20 |
1 u + 20 |
70 |
(a)
Total age of Bryan and Adam 20 years ago
= 70 - 40
= 30
20 years ago
Bryan's age = 5 u
Adam's age = 1 u
Total age of Bryan and Adam = 6 u
6 u + 40 = 70
6 u = 70 - 40 = 30
1 u = 30 ÷ 6 = 5
Bryan's age now
= 5 u + 20
= 5 x 5 + 20
= 25 + 20
= 45
(b)
Number of years that Bryan is older than Adam
= 5 u - 1 u
= 4 u
= 4 x 5
= 20
(c)
Adam's age in 25 years' time
= 1 u + 20 + 25
= 5 + 20 + 25
= 50
Answer(s): (a) 45; (b) 20; (c) 50
