Adam was 4 times as old as Bryan 15 years ago.
Their total present age is 85 years now.
- How old is Adam now?
- How many years is Adam older than Bryan?
- How old is Bryan in 10 years' time?
|
Adam |
Bryan |
Total |
15 years ago |
4 u |
1 u |
5 u |
Change |
+ 15 |
+ 15 |
+ 30 |
Present |
4 u + 15 |
1 u + 15 |
85 |
(a)
Total age of Adam and Bryan 15 years ago
= 85 - 30
= 55
15 years ago
Adam's age = 4 u
Bryan's age = 1 u
Total age of Adam and Bryan = 5 u
5 u + 30 = 85
5 u = 85 - 30 = 55
1 u = 55 ÷ 5 = 11
Adam's age now
= 4 u + 15
= 4 x 11 + 15
= 44 + 15
= 59
(b)
Number of years that Adam is older than Bryan
= 4 u - 1 u
= 3 u
= 3 x 11
= 33
(c)
Bryan's age in 10 years' time
= 1 u + 15 + 10
= 11 + 15 + 10
= 36
Answer(s): (a) 59; (b) 33; (c) 36