Adam receives his allowance of $160.
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 1 : 4.
- How much does Adam save?
- How much less does Adam spend on food than other expenses?
Spending |
Saving |
3 x 5 |
1 x 5 |
Food |
Other expenses |
|
1 x 3 |
4 x 3 |
|
3 u |
12 u |
5 u |
(a)
Adam's spending is the combined repeated identity.
Make the amount of spending the same using the LCM of 3 and 5.
LCM of 3 and 5 = 15
Total allowance
= 5 u + 15 u
= 20 u
20 u = 160
1 u = 160 ÷ 20 = 8
Amount that Adam saves
= 5 u
= 5 x 8
= $40
(b)
Amount that Adam spends less on food than other expenses
= 12 u - 3 u
= 9 u
= 9 x 8
= $72
Answer(s): (a) $40; (b) $72