PSLE Linda spent $475 in October. This amount was a 5% decrease from what she spent in September. The amount she spent in November was a 40% increase 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 |
- 5% |
|
October |
95% |
100 u |
Change |
|
+ 40 u |
November |
|
140 u |
(a)
Spending in September = 100%
Spending in October = 100% - 5% = 95%
95% = 475
1% = 475 ÷ 95 = 5
Spending in September
= 100%
= 100 x 5
= $500
Spending in October = 100 u
Spending in November = 100 u + 40 u = 140 u
100 u = 475
1 u = 475 ÷ 100 = 4.75
Spending in November
= 140 u
= 140 x 4.75
= $665
Total spending from September to November
= 500 + 475 + 665
= $1640
(b)
Increase in spending in November compared to September
= 665 - 500
= $165
Percentage increase
=
Increase in spendingSpending in September x 100%
=
165500 x 100%
= 33%
Answer(s): (a) $1640; (b) 33%