PSLE Linda spent $360 in October. This amount was a 40% 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 |
- 40% |
|
October |
60% |
100 u |
Change |
|
+ 30 u |
November |
|
130 u |
(a)
Spending in September = 100%
Spending in October = 100% - 40% = 60%
60% = 360
1% = 360 ÷ 60 = 6
Spending in September
= 100%
= 100 x 6
= $600
Spending in October = 100 u
Spending in November = 100 u + 30 u = 130 u
100 u = 360
1 u = 360 ÷ 100 = 3.6
Spending in November
= 130 u
= 130 x 3.6
= $468
Total spending from September to November
= 600 + 360 + 468
= $1428
(b)
Decrease in spending in November compared to September
= 600 - 468
= $132
Percentage decrease
=
Decrease in spendingSpending in September x 100%
=
132600 x 100%
= 22%
Answer(s): (a) $1428; (b) 22%