Adam was 4 times as old as Bryan 5 years ago.
Their total present age is 75 years now.
- How old is Adam now?
- How many years is Adam older than Bryan?
- How old is Bryan in 25 years' time?
| |
Adam |
Bryan |
Total |
| 5 years ago |
4 u |
1 u |
5 u |
| Change |
+ 5 |
+ 5 |
+ 10 |
| Present |
4 u + 5 |
1 u + 5 |
75 |
(a)
Total age of Adam and Bryan 5 years ago
= 75 - 10
= 65
5 years ago
Adam's age = 4 u
Bryan's age = 1 u
Total age of Adam and Bryan = 5 u
5 u + 10 = 75
5 u = 75 - 10 = 65
1 u = 65 ÷ 5 = 13
Adam's age now
= 4 u + 5
= 4 x 13 + 5
= 52 + 5
= 57
(b)
Number of years that Adam is older than Bryan
= 4 u - 1 u
= 3 u
= 3 x 13
= 39
(c)
Bryan's age in 25 years' time
= 1 u + 5 + 25
= 13 + 5 + 25
= 43
Answer(s): (a) 57; (b) 39; (c) 43
