PSLE Linda spent $220 in August. This amount was a 10% increase from what she spent in July. The amount she spent in September was a 40% decrease from what she spent in August.
- What was the total amount that Linda spent from July to September?
- What was the percentage decrease in the amount Linda spent in September compared to July?
|
Spending |
July |
100% |
|
Change |
+ 10% |
|
August |
110% |
100 u |
Change |
|
- 40 u |
September |
|
60 u |
(a)
Spending in July = 100%
Spending in August = 100% + 10% = 110%
110% = 220
1% = 220 ÷ 110 = 2
Spending in July
= 100%
= 100 x 2
= $200
Spending in August = 100 u
Spending in September = 100 u - 40 u = 60 u
100 u = 220
1 u = 220 ÷ 100 = 2.2
Spending in September
= 60 u
= 60 x 2.2
= $132
Total spending from July to September
= 200 + 220 + 132
= $552
(b)
Decrease in spending in September compared to July
= 200 - 132
= $68
Percentage decrease
=
Decrease in spendingSpending in July x 100%
=
68200 x 100%
= 34%
Answer(s): (a) $552; (b) 34%