PSLE Linda saved $320 in September. This amount was a 20% decrease from what she saved in August. The amount she saved in October was a 10% increase from what she saved in September.
- What was the total amount that Linda saved from August to October?
- What was the percentage decrease in the amount Linda saved in October compared to August?
|
Savings |
August |
100% |
|
Change |
- 20% |
|
September |
80% |
100 u |
Change |
|
+ 10 u |
October |
|
110 u |
(a)
Savings in August = 100%
Savings in September = 100% - 20% = 80%
80% = 320
1% = 320 ÷ 80 = 4
Savings in August
= 100%
= 100 x 4
= $400
Savings in September = 100 u
Savings in October = 100 u + 10 u = 110 u
100 u = 320
1 u = 320 ÷ 100 = 3.2
Savings in October
= 110 u
= 110 x 3.2
= $352
Total savings from August to October
= 400 + 320 + 352
= $1072
(b)
Decrease in savings in October compared to August
= 400 - 352
= $48
Percentage decrease
=
Decrease in savingsSavings in August x 100%
=
48400 x 100%
= 12%
Answer(s): (a) $1072; (b) 12%