PSLE Linda spent $330 in October. This amount was a 10% increase from what she spent in September. The amount she spent in November was a 50% decrease 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 |
+ 10% |
|
October |
110% |
100 u |
Change |
|
- 50 u |
November |
|
50 u |
(a)
Spending in September = 100%
Spending in October = 100% + 10% = 110%
110% = 330
1% = 330 ÷ 110 = 3
Spending in September
= 100%
= 100 x 3
= $300
Spending in October = 100 u
Spending in November = 100 u - 50 u = 50 u
100 u = 330
1 u = 330 ÷ 100 = 3.3
Spending in November
= 50 u
= 50 x 3.3
= $165
Total spending from September to November
= 300 + 330 + 165
= $795
(b)
Decrease in spending in November compared to September
= 300 - 165
= $135
Percentage decrease
=
Decrease in spendingSpending in September x 100%
=
135300 x 100%
= 45%
Answer(s): (a) $795; (b) 45%