Adam receives his allowance of $420.
The ratio of Adam's spending to Adam's saving is 5 : 2.
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 |
5 x 2 |
2 x 2 |
Food |
Other expenses |
|
3 x 1 |
7 x 1 |
|
3 u |
7 u |
4 u |
(a)
Adam's spending is the combined repeated identity.
Make the amount of spending the same using the LCM of 5 and 10.
LCM of 5 and 10 = 10
Total allowance
= 4 u + 10 u
= 14 u
14 u = 420
1 u = 420 ÷ 14 = 30
Amount that Adam saves
= 4 u
= 4 x 30
= $120
(b)
Amount that Adam spends more on other expenses than food
= 7 u - 3 u
= 4 u
= 4 x 30
= $120
Answer(s): (a) $120; (b) $120