PSLE Linda saved $300 in August. This amount was a 40% decrease from what she saved in July. The amount she saved in September was a 30% increase from what she saved in August.
- What was the total amount that Linda saved from July to September?
- What was the percentage decrease in the amount Linda saved in September compared to July?
|
Savings |
July |
100% |
|
Change |
- 40% |
|
August |
60% |
100 u |
Change |
|
+ 30 u |
September |
|
130 u |
(a)
Savings in July = 100%
Savings in August = 100% - 40% = 60%
60% = 300
1% = 300 ÷ 60 = 5
Savings in July
= 100%
= 100 x 5
= $500
Savings in August = 100 u
Savings in September = 100 u + 30 u = 130 u
100 u = 300
1 u = 300 ÷ 100 = 3
Savings in September
= 130 u
= 130 x 3
= $390
Total savings from July to September
= 500 + 300 + 390
= $1190
(b)
Decrease in savings in September compared to July
= 500 - 390
= $110
Percentage decrease
=
Decrease in savingsSavings in July x 100%
=
110500 x 100%
= 22%
Answer(s): (a) $1190; (b) 22%