PSLE Linda saved $420 in August. This amount was a 40% decrease from what she saved in July. The amount she saved in September was a 15% 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 |
|
+ 15 u |
September |
|
115 u |
(a)
Savings in July = 100%
Savings in August = 100% - 40% = 60%
60% = 420
1% = 420 ÷ 60 = 7
Savings in July
= 100%
= 100 x 7
= $700
Savings in August = 100 u
Savings in September = 100 u + 15 u = 115 u
100 u = 420
1 u = 420 ÷ 100 = 4.2
Savings in September
= 115 u
= 115 x 4.2
= $483
Total savings from July to September
= 700 + 420 + 483
= $1603
(b)
Decrease in savings in September compared to July
= 700 - 483
= $217
Percentage decrease
=
Decrease in savingsSavings in July x 100%
=
217700 x 100%
= 31%
Answer(s): (a) $1603; (b) 31%