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