Harry is 30 years older than his son. 12 years from now, his son will be
12 of his age while his child will be
35 of his son. Express his child’s present age as a fraction of Harry's present age. Leave your answer in its simplest form.
| |
Harry |
Harry's son |
Harry's child |
Difference between
Harry and Harry's son |
| Before |
10 u - 12 |
5 u - 12 |
3 u - 12 |
30 |
| Change |
+ 12 |
+ 12 |
+ 12 |
|
After
|
2x5 |
1x5 |
|
|
| |
5x1 |
3x1 |
|
Comparing Harry, his son and his child
in the end |
10 u |
5 u |
3 u |
5 u |
The repeated identity is the age of Harry's son. LCM of 1 and 5 is 5.
The difference in age between Harry and Harry's son remains unchanged.
Difference in age between Harry and Harry's son
= 10 u - 5 u
= 5 u
5 u = 30
1 u = 30 ÷ 5 = 6
His child's present age
= 3 u - 12
= 3 x 6 - 12
= 18 - 12
= 6
Harry's present age
= 10 u - 12
= 10 x 6 - 12
= 60 - 12
= 48
His child's present age as a fraction of Harry's present age
=
648=
18 Answer(s):
18 
