Adam was 5 times as old as Bryan 30 years ago.
Their total present age is 90 years now.
- How old is Adam now?
- How many years is Adam older than Bryan?
- How old is Bryan in 15 years' time?
|
Adam |
Bryan |
Total |
30 years ago |
5 u |
1 u |
6 u |
Change |
+ 30 |
+ 30 |
+ 60 |
Present |
5 u + 30 |
1 u + 30 |
90 |
(a)
Total age of Adam and Bryan 30 years ago
= 90 - 60
= 30
30 years ago
Adam's age = 5 u
Bryan's age = 1 u
Total age of Adam and Bryan = 6 u
6 u + 60 = 90
6 u = 90 - 60 = 30
1 u = 30 ÷ 6 = 5
Adam's age now
= 5 u + 30
= 5 x 5 + 30
= 25 + 30
= 55
(b)
Number of years that Adam is older than Bryan
= 5 u - 1 u
= 4 u
= 4 x 5
= 20
(c)
Bryan's age in 15 years' time
= 1 u + 30 + 15
= 5 + 30 + 15
= 50
Answer(s): (a) 55; (b) 20; (c) 50