PSLE
Linda spent $720 in November. This amount was a 20% increase from what she spent in October. The amount she spent in December was a 5% decrease from what she spent in November.

1. What was the total amount that Linda spent from October to December?
2. What was the percentage increase in the amount Linda spent in December compared to October?

	Spending
October	100%
Change	+ 20%
November	120%	100 u
Change		- 5 u
December		95 u

(a)
Spending in October = 100%
Spending in November = 100% + 20% = 120%

120% = 720

1% = 720 ÷ 120 = 6

Spending in October
= 100% 
= 100 x 6
= $600

Spending in November = 100 u
Spending in December = 100 u - 5 u = 95 u 

100 u = 720

1 u = 720 ÷ 100 = 7.2

Spending in December
= 95 u
= 95 x 7.2
= $684

Total spending from October to December
= 600 + 720 + 684
= $2004

(b)
Increase in spending in December compared to October
= 684 - 600
= $84

Percentage increase
= ^{Increase in spending}_{Spending in October} x 100%
= ⁸⁴₆₀₀ x 100%
= 14%

Answer(s): (a) $2004; (b) 14%