PSLE Linda spent $180 in November. This amount was a 40% decrease from what she spent in October. The amount she spent in December was a 25% increase from what she spent in November.
- What was the total amount that Linda spent from October to December?
- What was the percentage decrease in the amount Linda spent in December compared to October?
|
Spending |
October |
100% |
|
Change |
- 40% |
|
November |
60% |
100 u |
Change |
|
+ 25 u |
December |
|
125 u |
(a)
Spending in October = 100%
Spending in November = 100% - 40% = 60%
60% = 180
1% = 180 ÷ 60 = 3
Spending in October
= 100%
= 100 x 3
= $300
Spending in November = 100 u
Spending in December = 100 u + 25 u = 125 u
100 u = 180
1 u = 180 ÷ 100 = 1.8
Spending in December
= 125 u
= 125 x 1.8
= $225
Total spending from October to December
= 300 + 180 + 225
= $705
(b)
Decrease in spending in December compared to October
= 300 - 225
= $75
Percentage decrease
=
Decrease in spendingSpending in October x 100%
=
75300 x 100%
= 25%
Answer(s): (a) $705; (b) 25%