Tammy is 5 years old. Her mother is 38 years old. How old will Tammy be when her mother is four times her age?
| |
Tammy |
Her mother |
Difference |
| Before |
5 |
38 |
33 |
| Change |
+ ? |
+ ? |
|
| After |
1 u |
4 u |
3 u |
The difference in the age between Tammy and her mother remains unchanged.
Difference in their age at first
= 38 - 5
= 33
Difference in their age in the end
= 4 u - 1 u
= 3 u
3 u = 33
1 u = 33 ÷ 3 = 11
Tammy's age when her mother is four times her age
= 1 u
= 11
Answer(s): 11
