Adam was 4 times as old as Bryan 25 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 10 years' time?
|
Adam |
Bryan |
Total |
25 years ago |
4 u |
1 u |
5 u |
Change |
+ 25 |
+ 25 |
+ 50 |
Present |
4 u + 25 |
1 u + 25 |
75 |
(a)
Total age of Adam and Bryan 25 years ago
= 75 - 50
= 25
25 years ago
Adam's age = 4 u
Bryan's age = 1 u
Total age of Adam and Bryan = 5 u
5 u + 50 = 75
5 u = 75 - 50 = 25
1 u = 25 ÷ 5 = 5
Adam's age now
= 4 u + 25
= 4 x 5 + 25
= 20 + 25
= 45
(b)
Number of years that Adam is older than Bryan
= 4 u - 1 u
= 3 u
= 3 x 5
= 15
(c)
Bryan's age in 10 years' time
= 1 u + 25 + 10
= 5 + 25 + 10
= 40
Answer(s): (a) 45; (b) 15; (c) 40