Adam receives his allowance of $162.
The ratio of Adam's spending to Adam's saving is 5 : 4.
The ratio of Adam's spending on food to the remaining of other expenses is 3 : 7.
- How much does Adam save?
- How much less does Adam spend on food than other expenses?
Spending |
Saving |
5 x 2 |
4 x 2 |
Food |
Other expenses |
|
3 x 1 |
7 x 1 |
|
3 u |
7 u |
8 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
= 8 u + 10 u
= 18 u
18 u = 162
1 u = 162 ÷ 18 = 9
Amount that Adam saves
= 8 u
= 8 x 9
= $72
(b)
Amount that Adam spends less on food than other expenses
= 7 u - 3 u
= 4 u
= 4 x 9
= $36
Answer(s): (a) $72; (b) $36