When Mr Ahmad is 45 years old, his niece is 9 years old. In how many years will he be 4 times as old as his niece?
| |
Mr Ahmad |
His niece |
Difference |
| Before |
45 |
9 |
36 |
| Change |
+ ? |
+ ? |
|
| After |
4 u |
1 u |
3 u |
The difference in the age between Mr Ahmad and his niece at first and in the end remains the same.
Difference in the age between Mr Ahmad and his niece
= 4 u - 1 u
= 3 u
3 u = 45 - 9
3 u = 36
1 u = 36 ÷ 3 = 12
Number of years' time so Mr Ahmad will be 4 times as old as his niece
= 12 - 9
= 3
Answer(s): 3
