In October, Perry gave his wife, Raeann, $4000 for household expenditure. Raeann spent 50% of the sum on rental, 20% on food and saved the rest. In November, Perry reduced the sum he gave to Raeann. Raeann spent the same amount on rental and reduced the amount she spent on food by 20%. She saved the remaining 20% of the sum given to her in November. By what percentage was the sum given to Raeann reduced by?

	Rental	Food	Savings	Total
Before	50%	20%	30%	$4000
Change		- 4%	- ?	- ?
After	50%	16%
Comparing the amounts spent in November	80 u		20 u	100 u

Amount that Perry saved in percent
= 100% - 50% - 20%
= 30%

Amount that Perry reduced on food in percent
= 20% x 20%
= ²⁰₁₀₀ x 20
= 4%

Total amount that Perry spent on rental and food in percent
= 50% + 16%
= 66%

100% → 4000

1% → 4000 ÷ 100 = 40

66% → 66 x  40 = 2640

The total amount that Perry spent on rental and food is repeated. 

80 u = 66% 

80 u = 2640

1 u = 2640 ÷ 80 = 33

Amount that Perry gave to Raeann in November
= 100 u
= 100 x 33
= $3300

Amount that Raeann received less from Perry from October to November
= 4000 - 3300
= $700

Percentage that the sum given to Raeann was reduced by from October to November
= ⁷⁰⁰₄₀₀₀ x 100%
= 17.5%

Answer(s): 17.5%