PSLE Linda spent $200 in October. This amount was a 50% decrease from what she spent in September. The amount she spent in November was a 30% increase from what she spent in October.
- What was the total amount that Linda spent from September to November?
- What was the percentage decrease in the amount Linda spent in November compared to September?
|
Spending |
September |
100% |
|
Change |
- 50% |
|
October |
50% |
100 u |
Change |
|
+ 30 u |
November |
|
130 u |
(a)
Spending in September = 100%
Spending in October = 100% - 50% = 50%
50% = 200
1% = 200 ÷ 50 = 4
Spending in September
= 100%
= 100 x 4
= $400
Spending in October = 100 u
Spending in November = 100 u + 30 u = 130 u
100 u = 200
1 u = 200 ÷ 100 = 2
Spending in November
= 130 u
= 130 x 2
= $260
Total spending from September to November
= 400 + 200 + 260
= $860
(b)
Decrease in spending in November compared to September
= 400 - 260
= $140
Percentage decrease
=
Decrease in spendingSpending in September x 100%
=
140400 x 100%
= 35%
Answer(s): (a) $860; (b) 35%