PSLE Linda saved $360 in November. This amount was a 20% increase from what she saved in October. The amount she saved in December was a 25% decrease from what she saved in November.
- What was the total amount that Linda saved from October to December?
- What was the percentage decrease in the amount Linda saved in December compared to October?
|
Savings |
October |
100% |
|
Change |
+ 20% |
|
November |
120% |
100 u |
Change |
|
- 25 u |
December |
|
75 u |
(a)
Savings in October = 100%
Savings in November = 100% + 20% = 120%
120% = 360
1% = 360 ÷ 120 = 3
Savings in October
= 100%
= 100 x 3
= $300
Savings in November = 100 u
Savings in December = 100 u - 25 u = 75 u
100 u = 360
1 u = 360 ÷ 100 = 3.6
Savings in December
= 75 u
= 75 x 3.6
= $270
Total savings from October to December
= 300 + 360 + 270
= $930
(b)
Decrease in savings in December compared to October
= 300 - 270
= $30
Percentage decrease
=
Decrease in savingsSavings in October x 100%
=
30300 x 100%
= 10%
Answer(s): (a) $930; (b) 10%