When Mr Cole is 22 years old, his son is 2 years old. In how many years will he be 3 times as old as his son?
|
Mr Cole |
His son |
Difference |
Before |
22 |
2 |
20 |
Change |
+ ? |
+ ? |
|
After |
3 u |
1 u |
2 u |
The difference in the age between Mr Cole and his son at first and in the end remains the same.
Difference in the age between Mr Cole and his son
= 3 u - 1 u
= 2 u
2 u = 22 - 2
2 u = 20
1 u = 20 ÷ 2 = 10
Number of years' time so Mr Cole will be 3 times as old as his son
= 10 - 2
= 8
Answer(s): 8