PSLE Linda spent $700 in November. This amount was a 40% increase from what she spent in October. The amount she spent in December was a 15% decrease from what she spent in November.
- What was the total amount that Linda spent from October to December?
- What was the percentage increase in the amount Linda spent in December compared to October?
|
Spending |
October |
100% |
|
Change |
+ 40% |
|
November |
140% |
100 u |
Change |
|
- 15 u |
December |
|
85 u |
(a)
Spending in October = 100%
Spending in November = 100% + 40% = 140%
140% = 700
1% = 700 ÷ 140 = 5
Spending in October
= 100%
= 100 x 5
= $500
Spending in November = 100 u
Spending in December = 100 u - 15 u = 85 u
100 u = 700
1 u = 700 ÷ 100 = 7
Spending in December
= 85 u
= 85 x 7
= $595
Total spending from October to December
= 500 + 700 + 595
= $1795
(b)
Increase in spending in December compared to October
= 595 - 500
= $95
Percentage increase
=
Increase in spendingSpending in October x 100%
=
95500 x 100%
= 19%
Answer(s): (a) $1795; (b) 19%