Mrs Tang is 38 years old and her child is 6 years old now. In how many years' time will Mrs Tang be thrice as old as her child?
| |
Mrs Tang |
Her child |
Difference |
| Before |
38 |
6 |
32 |
| Change |
+ ? |
+ ? |
|
| After |
3 u |
1 u |
2 u |
The difference in the age between Mrs Tang and her child remains unchanged.
Difference in their age at first
= 38 - 6
= 32
Difference in their age in the end
= 3 u - 1 u
= 2 u
2 u = 32
1 u = 32 ÷ 2 = 16
Number of years time that Mrs Tang will be thrice as old as her child
= 1 u - 6
= 16 - 6
= 10
Answer(s): 10
