Adam is 9 times as old as Bryan now.
In 10 years time, their total age is 90 years.
How old is Adam now?
- How old is Bryan now?
- How many years is Bryan younger than Adam?
- How old was Adam 31 years ago?
|
Adam |
Bryan |
Total |
Now |
9 u |
1 u |
10 u |
Change |
+ 10 |
+ 10 |
+ 20 |
10 years later |
9 u + 10 |
1 u + 10 |
90 |
(a)
Total age of Adam and Bryan now
= 90 - 20
= 70
Now
Adam's age = 9 u
Bryan's age = 1 u
Total age of Adam and Bryan = 10 u
10 u = 70
1 u = 70 ÷ 10 = 7
Bryan's age now
= 1 u
= 7
(b)
Number of years that Bryan is younger than Adam
= 9 u - 1 u
= 8 u
= 8 x 7
= 56
(c)
Adam's age 31 years' ago
= 9 u - 31
= 9 x 7 - 31
= 63 - 31
= 32
Answer(s): (a) 7; (b) 56; (c) 32