PSLE Linda spent $350 in November. This amount was a 50% decrease from what she spent in October. The amount she spent in December was a 10% increase from what she spent in November.
- What was the total amount that Linda spent from October to December?
- What was the percentage decrease in the amount Linda spent in December compared to October?
|
Spending |
October |
100% |
|
Change |
- 50% |
|
November |
50% |
100 u |
Change |
|
+ 10 u |
December |
|
110 u |
(a)
Spending in October = 100%
Spending in November = 100% - 50% = 50%
50% = 350
1% = 350 ÷ 50 = 7
Spending in October
= 100%
= 100 x 7
= $700
Spending in November = 100 u
Spending in December = 100 u + 10 u = 110 u
100 u = 350
1 u = 350 ÷ 100 = 3.5
Spending in December
= 110 u
= 110 x 3.5
= $385
Total spending from October to December
= 700 + 350 + 385
= $1435
(b)
Decrease in spending in December compared to October
= 700 - 385
= $315
Percentage decrease
=
Decrease in spendingSpending in October x 100%
=
315700 x 100%
= 45%
Answer(s): (a) $1435; (b) 45%