When Mr Riordan is 38 years old, his son is 6 years old. In how many years will he be 5 times as old as his son?
| |
Mr Riordan |
His son |
Difference |
| Before |
38 |
6 |
32 |
| Change |
+ ? |
+ ? |
|
| After |
5 u |
1 u |
4 u |
The difference in the age between Mr Riordan and his son at first and in the end remains the same.
Difference in the age between Mr Riordan and his son
= 5 u - 1 u
= 4 u
4 u = 38 - 6
4 u = 32
1 u = 32 ÷ 4 = 8
Number of years' time so Mr Riordan will be 5 times as old as his son
= 8 - 6
= 2
Answer(s): 2
