PSLE Linda spent $200 in February. This amount was a 50% decrease from what she spent in January. The amount she spent in March was a 50% increase from what she spent in February.
- What was the total amount that Linda spent from January to March?
- What was the percentage decrease in the amount Linda spent in March compared to January?
|
Spending |
January |
100% |
|
Change |
- 50% |
|
February |
50% |
100 u |
Change |
|
+ 50 u |
March |
|
150 u |
(a)
Spending in January = 100%
Spending in February = 100% - 50% = 50%
50% = 200
1% = 200 ÷ 50 = 4
Spending in January
= 100%
= 100 x 4
= $400
Spending in February = 100 u
Spending in March = 100 u + 50 u = 150 u
100 u = 200
1 u = 200 ÷ 100 = 2
Spending in March
= 150 u
= 150 x 2
= $300
Total spending from January to March
= 400 + 200 + 300
= $900
(b)
Decrease in spending in March compared to January
= 400 - 300
= $100
Percentage decrease
=
Decrease in spendingSpending in January x 100%
=
100400 x 100%
= 25%
Answer(s): (a) $900; (b) 25%