PSLE Linda spent $600 in February. This amount was a 20% increase from what she spent in January. The amount she spent in March was a 10% decrease 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 |
120% |
100 u |
Change |
|
- 10 u |
March |
|
90 u |
(a)
Spending in January = 100%
Spending in February = 100% + 20% = 120%
120% = 600
1% = 600 ÷ 120 = 5
Spending in January
= 100%
= 100 x 5
= $500
Spending in February = 100 u
Spending in March = 100 u - 10 u = 90 u
100 u = 600
1 u = 600 ÷ 100 = 6
Spending in March
= 90 u
= 90 x 6
= $540
Total spending from January to March
= 500 + 600 + 540
= $1640
(b)
Increase in spending in March compared to January
= 540 - 500
= $40
Percentage increase
=
Increase in spendingSpending in January x 100%
=
40500 x 100%
= 8%
Answer(s): (a) $1640; (b) 8%