PSLE Linda spent $480 in August. This amount was a 40% decrease from what she spent in July. The amount she spent in September was a 5% increase 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 |
- 40% |
|
August |
60% |
100 u |
Change |
|
+ 5 u |
September |
|
105 u |
(a)
Spending in July = 100%
Spending in August = 100% - 40% = 60%
60% = 480
1% = 480 ÷ 60 = 8
Spending in July
= 100%
= 100 x 8
= $800
Spending in August = 100 u
Spending in September = 100 u + 5 u = 105 u
100 u = 480
1 u = 480 ÷ 100 = 4.8
Spending in September
= 105 u
= 105 x 4.8
= $504
Total spending from July to September
= 800 + 480 + 504
= $1784
(b)
Decrease in spending in September compared to July
= 800 - 504
= $296
Percentage decrease
=
Decrease in spendingSpending in July x 100%
=
296800 x 100%
= 37%
Answer(s): (a) $1784; (b) 37%