Adam is 9 times as old as Bryan now.
In 15 years time, their total age is 70 years.
How old is Adam now?
- How old is Bryan now?
- How many years is Bryan younger than Adam?
- How old was Adam 16 years ago?
|
Adam |
Bryan |
Total |
Now |
9 u |
1 u |
10 u |
Change |
+ 15 |
+ 15 |
+ 30 |
15 years later |
9 u + 15 |
1 u + 15 |
70 |
(a)
Total age of Adam and Bryan now
= 70 - 30
= 40
Now
Adam's age = 9 u
Bryan's age = 1 u
Total age of Adam and Bryan = 10 u
10 u = 40
1 u = 40 ÷ 10 = 4
Bryan's age now
= 1 u
= 4
(b)
Number of years that Bryan is younger than Adam
= 9 u - 1 u
= 8 u
= 8 x 4
= 32
(c)
Adam's age 16 years' ago
= 9 u - 16
= 9 x 4 - 16
= 36 - 16
= 20
Answer(s): (a) 4; (b) 32; (c) 20