PSLE Linda saved $420 in October. This amount was a 40% decrease from what she saved in September. The amount she saved in November was a 30% increase from what she saved in October.
- What was the total amount that Linda saved from September to November?
- What was the percentage decrease in the amount Linda saved in November compared to September?
|
Savings |
September |
100% |
|
Change |
- 40% |
|
October |
60% |
100 u |
Change |
|
+ 30 u |
November |
|
130 u |
(a)
Savings in September = 100%
Savings in October = 100% - 40% = 60%
60% = 420
1% = 420 ÷ 60 = 7
Savings in September
= 100%
= 100 x 7
= $700
Savings in October = 100 u
Savings in November = 100 u + 30 u = 130 u
100 u = 420
1 u = 420 ÷ 100 = 4.2
Savings in November
= 130 u
= 130 x 4.2
= $546
Total savings from September to November
= 700 + 420 + 546
= $1666
(b)
Decrease in savings in November compared to September
= 700 - 546
= $154
Percentage decrease
=
Decrease in savingsSavings in September x 100%
=
154700 x 100%
= 22%
Answer(s): (a) $1666; (b) 22%