Mrs Ng is 37 years old and her cousin is 11 years old now. In how many years' time will Mrs Ng be thrice as old as her cousin?
| |
Mrs Ng |
Her cousin |
Difference |
| Before |
37 |
11 |
26 |
| Change |
+ ? |
+ ? |
|
| After |
3 u |
1 u |
2 u |
The difference in the age between Mrs Ng and her cousin remains unchanged.
Difference in their age at first
= 37 - 11
= 26
Difference in their age in the end
= 3 u - 1 u
= 2 u
2 u = 26
1 u = 26 ÷ 2 = 13
Number of years time that Mrs Ng will be thrice as old as her cousin
= 1 u - 11
= 13 - 11
= 2
Answer(s): 2
