Zara was 7 years old last year. She was 26 years younger than Irene.
- How old will her Irene be 4 years later?
- In how many years' time will Zara's age be 13 of Irene's age?
| |
Zara |
Irene |
Difference |
| Before (Last year) |
7 |
33 |
26 |
| Change 1 |
+ 1 |
+ 1 |
|
| After 1 (Now) |
8 |
34 |
26 |
| Change 2 |
+ 4 |
+ 4 |
|
| After 2 (4 years later) |
|
? |
26 |
(a)
Irene's age this year
= 7 + 26
= 33
Irene's age this year
= 33 + 1
= 34
Irene's age in 4 years' time
= 34 + 4
= 38
| |
Zara |
Irene |
Difference |
| Before |
8 |
34 |
26 |
| Change |
+ ? |
+ ? |
|
| After |
1 u |
3 u |
2 u |
(b)
The difference in the age between Zara and Irene at first and in the end remains unchanged.
Difference in the age between Zara and Irene
= 3 u - 1 u
= 2 u
2 u = 26
1 u = 26 ÷ 2 = 13
Number of years' time that Zara's age be
13 of Irene's age
= 13 - 8
= 5
Answer(s): (a) 38; (b) 5
