Adam receives his allowance of $200.
The ratio of Adam's spending to Adam's saving is 3 : 1.
The ratio of Adam's spending on food to the remaining of other expenses is 3 : 7.
- How much does Adam save?
- How much more does Adam spend on other expenses than food?
Spending |
Saving |
3 x 10 |
1 x 10 |
Food |
Other expenses |
|
3 x 3 |
7 x 3 |
|
9 u |
21 u |
10 u |
(a)
Adam's spending is the combined repeated identity.
Make the amount of spending the same using the LCM of 3 and 10.
LCM of 3 and 10 = 30
Total allowance
= 10 u + 30 u
= 40 u
40 u = 200
1 u = 200 ÷ 40 = 5
Amount that Adam saves
= 10 u
= 10 x 5
= $50
(b)
Amount that Adam spends more on other expenses than food
= 21 u - 9 u
= 12 u
= 12 x 5
= $60
Answer(s): (a) $50; (b) $60