Mrs Yap is 62 years old and her niece is 11 years old now. In how many years' time will Mrs Yap be four times as old as her niece?
| |
Mrs Yap |
Her niece |
Difference |
| Before |
62 |
11 |
51 |
| Change |
+ ? |
+ ? |
|
| After |
4 u |
1 u |
3 u |
The difference in the age between Mrs Yap and her niece remains unchanged.
Difference in their age at first
= 62 - 11
= 51
Difference in their age in the end
= 4 u - 1 u
= 3 u
3 u = 51
1 u = 51 ÷ 3 = 17
Number of years time that Mrs Yap will be four times as old as her niece
= 1 u - 11
= 17 - 11
= 6
Answer(s): 6
