When Mr Luis is 30 years old, his daughter is 3 years old. In how many years will he be 4 times as old as his daughter?
| |
Mr Luis |
His daughter |
Difference |
| Before |
30 |
3 |
27 |
| Change |
+ ? |
+ ? |
|
| After |
4 u |
1 u |
3 u |
The difference in the age between Mr Luis and his daughter at first and in the end remains the same.
Difference in the age between Mr Luis and his daughter
= 4 u - 1 u
= 3 u
3 u = 30 - 3
3 u = 27
1 u = 27 ÷ 3 = 9
Number of years' time so Mr Luis will be 4 times as old as his daughter
= 9 - 3
= 6
Answer(s): 6
