Adam is 3 times as old as Bryan now.
In 20 years time, their total age is 80 years.
How old is Adam now?
- How old is Bryan now?
- How many years is Bryan younger than Adam?
- How old was Adam 12 years ago?
|
Adam |
Bryan |
Total |
Now |
3 u |
1 u |
4 u |
Change |
+ 20 |
+ 20 |
+ 40 |
20 years later |
3 u + 20 |
1 u + 20 |
80 |
(a)
Total age of Adam and Bryan now
= 80 - 40
= 40
Now
Adam's age = 3 u
Bryan's age = 1 u
Total age of Adam and Bryan = 4 u
4 u = 40
1 u = 40 ÷ 4 = 10
Bryan's age now
= 1 u
= 10
(b)
Number of years that Bryan is younger than Adam
= 3 u - 1 u
= 2 u
= 2 x 10
= 20
(c)
Adam's age 12 years' ago
= 3 u - 12
= 3 x 10 - 12
= 30 - 12
= 18
Answer(s): (a) 10; (b) 20; (c) 18