Zeph is 5 years old. His father is 26 years older than him. In how many years will Zeph's father be 3 times as old as Zeph?
| |
His father |
Zeph |
Difference |
| Before |
31 |
5 |
26 |
| Change |
+ ? |
+ ? |
|
| After |
3 u |
1 u |
2 u |
The difference in the age between Zeph and his father at first and in the end remains the same.
Difference in the age between Zeph and his father
= 3 u - 1 u
= 2 u
2 u = 26
1 u = 26 ÷ 2 = 13
The increase in age of Zeph and his father remains the same.
Number of years' time so Zeph's father will be 3 times as old as Zeph
= 13 - 5
= 8
Answer(s): 8
