Nora was 10 years old last year. She was 24 years younger than Lucy.
- How old will her Lucy be 3 years later?
- In how many years' time will Nora's age be 13 of Lucy's age?
|
Nora |
Lucy |
Difference |
Before (Last year) |
10 |
34 |
24 |
Change 1 |
+ 1 |
+ 1 |
|
After 1 (Now) |
11 |
35 |
24 |
Change 2 |
+ 3 |
+ 3 |
|
After 2 (3 years later) |
|
? |
24 |
(a)
Lucy's age this year
= 10 + 24
= 34
Lucy's age this year
= 34 + 1
= 35
Lucy's age in 3 years' time
= 35 + 3
= 38
|
Nora |
Lucy |
Difference |
Before |
11 |
35 |
24 |
Change |
+ ? |
+ ? |
|
After |
1 u |
3 u |
2 u |
(b)
The difference in the age between Nora and Lucy at first and in the end remains unchanged.
Difference in the age between Nora and Lucy
= 3 u - 1 u
= 2 u
2 u = 24
1 u = 24 ÷ 2 = 12
Number of years' time that Nora's age be
13 of Lucy's age
= 12 - 11
= 1
Answer(s): (a) 38; (b) 1