Fanny was 8 years old last year. She was 24 years younger than Tammy.
- How old will her Tammy be 7 years later?
- In how many years' time will Fanny's age be 13 of Tammy's age?
| |
Fanny |
Tammy |
Difference |
| Before (Last year) |
8 |
32 |
24 |
| Change 1 |
+ 1 |
+ 1 |
|
| After 1 (Now) |
9 |
33 |
24 |
| Change 2 |
+ 7 |
+ 7 |
|
| After 2 (7 years later) |
|
? |
24 |
(a)
Tammy's age this year
= 8 + 24
= 32
Tammy's age this year
= 32 + 1
= 33
Tammy's age in 7 years' time
= 33 + 7
= 40
| |
Fanny |
Tammy |
Difference |
| Before |
9 |
33 |
24 |
| Change |
+ ? |
+ ? |
|
| After |
1 u |
3 u |
2 u |
(b)
The difference in the age between Fanny and Tammy at first and in the end remains unchanged.
Difference in the age between Fanny and Tammy
= 3 u - 1 u
= 2 u
2 u = 24
1 u = 24 ÷ 2 = 12
Number of years' time that Fanny's age be
13 of Tammy's age
= 12 - 9
= 3
Answer(s): (a) 40; (b) 3
