Bryan was 3 times as old as Adam 10 years ago.
Their total present age is 80 years now.
- How old is Bryan now?
- How many years is Bryan older than Adam?
- How old is Adam in 10 years' time?
|
Bryan |
Adam |
Total |
10 years ago |
3 u |
1 u |
4 u |
Change |
+ 10 |
+ 10 |
+ 20 |
Present |
3 u + 10 |
1 u + 10 |
80 |
(a)
Total age of Bryan and Adam 10 years ago
= 80 - 20
= 60
10 years ago
Bryan's age = 3 u
Adam's age = 1 u
Total age of Bryan and Adam = 4 u
4 u + 20 = 80
4 u = 80 - 20 = 60
1 u = 60 ÷ 4 = 15
Bryan's age now
= 3 u + 10
= 3 x 15 + 10
= 45 + 10
= 55
(b)
Number of years that Bryan is older than Adam
= 3 u - 1 u
= 2 u
= 2 x 15
= 30
(c)
Adam's age in 10 years' time
= 1 u + 10 + 10
= 15 + 10 + 10
= 35
Answer(s): (a) 55; (b) 30; (c) 35