PSLE Linda spent $440 in September. This amount was a 10% increase from what she spent in August. The amount she spent in October was a 20% decrease from what she spent in September.
- What was the total amount that Linda spent from August to October?
- What was the percentage decrease in the amount Linda spent in October compared to August?
|
Spending |
August |
100% |
|
Change |
+ 10% |
|
September |
110% |
100 u |
Change |
|
- 20 u |
October |
|
80 u |
(a)
Spending in August = 100%
Spending in September = 100% + 10% = 110%
110% = 440
1% = 440 ÷ 110 = 4
Spending in August
= 100%
= 100 x 4
= $400
Spending in September = 100 u
Spending in October = 100 u - 20 u = 80 u
100 u = 440
1 u = 440 ÷ 100 = 4.4
Spending in October
= 80 u
= 80 x 4.4
= $352
Total spending from August to October
= 400 + 440 + 352
= $1192
(b)
Decrease in spending in October compared to August
= 400 - 352
= $48
Percentage decrease
=
Decrease in spendingSpending in August x 100%
=
48400 x 100%
= 12%
Answer(s): (a) $1192; (b) 12%