PSLE Linda spent $630 in February. This amount was a 30% decrease from what she spent in January. The amount she spent in March was a 10% 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 |
- 30% |
|
February |
70% |
100 u |
Change |
|
+ 10 u |
March |
|
110 u |
(a)
Spending in January = 100%
Spending in February = 100% - 30% = 70%
70% = 630
1% = 630 ÷ 70 = 9
Spending in January
= 100%
= 100 x 9
= $900
Spending in February = 100 u
Spending in March = 100 u + 10 u = 110 u
100 u = 630
1 u = 630 ÷ 100 = 6.3
Spending in March
= 110 u
= 110 x 6.3
= $693
Total spending from January to March
= 900 + 630 + 693
= $2223
(b)
Decrease in spending in March compared to January
= 900 - 693
= $207
Percentage decrease
=
Decrease in spendingSpending in January x 100%
=
207900 x 100%
= 23%
Answer(s): (a) $2223; (b) 23%