Penelope was 5 years old last year. She was 28 years younger than Kylie.
- How old will her Kylie be 3 years later?
- In how many years' time will Penelope's age be 13 of Kylie's age?
| |
Penelope |
Kylie |
Difference |
| Before (Last year) |
5 |
33 |
28 |
| Change 1 |
+ 1 |
+ 1 |
|
| After 1 (Now) |
6 |
34 |
28 |
| Change 2 |
+ 3 |
+ 3 |
|
| After 2 (3 years later) |
|
? |
28 |
(a)
Kylie's age this year
= 5 + 28
= 33
Kylie's age this year
= 33 + 1
= 34
Kylie's age in 3 years' time
= 34 + 3
= 37
| |
Penelope |
Kylie |
Difference |
| Before |
6 |
34 |
28 |
| Change |
+ ? |
+ ? |
|
| After |
1 u |
3 u |
2 u |
(b)
The difference in the age between Penelope and Kylie at first and in the end remains unchanged.
Difference in the age between Penelope and Kylie
= 3 u - 1 u
= 2 u
2 u = 28
1 u = 28 ÷ 2 = 14
Number of years' time that Penelope's age be
13 of Kylie's age
= 14 - 6
= 8
Answer(s): (a) 37; (b) 8
