PSLE Linda spent $1170 in October. This amount was a 30% increase from what she spent in September. The amount she spent in November was a 50% decrease from what she spent in October.
- What was the total amount that Linda spent from September to November?
- What was the percentage decrease in the amount Linda spent in November compared to September?
|
Spending |
September |
100% |
|
Change |
+ 30% |
|
October |
130% |
100 u |
Change |
|
- 50 u |
November |
|
50 u |
(a)
Spending in September = 100%
Spending in October = 100% + 30% = 130%
130% = 1170
1% = 1170 ÷ 130 = 9
Spending in September
= 100%
= 100 x 9
= $900
Spending in October = 100 u
Spending in November = 100 u - 50 u = 50 u
100 u = 1170
1 u = 1170 ÷ 100 = 11.7
Spending in November
= 50 u
= 50 x 11.7
= $585
Total spending from September to November
= 900 + 1170 + 585
= $2655
(b)
Decrease in spending in November compared to September
= 900 - 585
= $315
Percentage decrease
=
Decrease in spendingSpending in September x 100%
=
315900 x 100%
= 35%
Answer(s): (a) $2655; (b) 35%