PSLE Linda spent $675 in October. This amount was a 35% increase from what she spent in September. The amount she spent in November was a 20% decrease from what she spent in October.
- What was the total amount that Linda spent from September to November?
- What was the percentage increase in the amount Linda spent in November compared to September?
|
Spending |
September |
100% |
|
Change |
+ 35% |
|
October |
135% |
100 u |
Change |
|
- 20 u |
November |
|
80 u |
(a)
Spending in September = 100%
Spending in October = 100% + 35% = 135%
135% = 675
1% = 675 ÷ 135 = 5
Spending in September
= 100%
= 100 x 5
= $500
Spending in October = 100 u
Spending in November = 100 u - 20 u = 80 u
100 u = 675
1 u = 675 ÷ 100 = 6.75
Spending in November
= 80 u
= 80 x 6.75
= $540
Total spending from September to November
= 500 + 675 + 540
= $1715
(b)
Increase in spending in November compared to September
= 540 - 500
= $40
Percentage increase
=
Increase in spendingSpending in September x 100%
=
40500 x 100%
= 8%
Answer(s): (a) $1715; (b) 8%