PSLE Linda spent $480 in February. This amount was a 20% decrease from what she spent in January. The amount she spent in March was a 40% increase from what she spent in February.
- What was the total amount that Linda spent from January to March?
- What was the percentage increase in the amount Linda spent in March compared to January?
|
Spending |
January |
100% |
|
Change |
- 20% |
|
February |
80% |
100 u |
Change |
|
+ 40 u |
March |
|
140 u |
(a)
Spending in January = 100%
Spending in February = 100% - 20% = 80%
80% = 480
1% = 480 ÷ 80 = 6
Spending in January
= 100%
= 100 x 6
= $600
Spending in February = 100 u
Spending in March = 100 u + 40 u = 140 u
100 u = 480
1 u = 480 ÷ 100 = 4.8
Spending in March
= 140 u
= 140 x 4.8
= $672
Total spending from January to March
= 600 + 480 + 672
= $1752
(b)
Increase in spending in March compared to January
= 672 - 600
= $72
Percentage increase
=
Increase in spendingSpending in January x 100%
=
72600 x 100%
= 12%
Answer(s): (a) $1752; (b) 12%