In June, Ken gave his wife, Jean, $8000 for household expenditure. Jean spent 50% of the sum on rental, 10% on food and saved the rest. In July, Ken reduced the sum he gave to Jean. Jean 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 July. By what percentage was the sum given to Jean reduced by?

	Rental	Food	Savings	Total
Before	50%	10%	40%	$8000
Change		- 2%	- ?	- ?
After	50%	8%
Comparing the amounts spent in July	80 u		20 u	100 u

Amount that Ken saved in percent
= 100% - 50% - 10%
= 40%

Amount that Ken reduced on food in percent
= 20% x 10%
= ²⁰₁₀₀ x 10
= 2%

Total amount that Ken spent on rental and food in percent
= 50% + 8%
= 58%

100% → 8000

1% → 8000 ÷ 100 = 80

58% → 58 x  80 = 4640

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

80 u = 58% 

80 u = 4640

1 u = 4640 ÷ 80 = 58

Amount that Ken gave to Jean in July
= 100 u
= 100 x 58
= $5800

Amount that Jean received less from Ken from June to July
= 8000 - 5800
= $2200

Percentage that the sum given to Jean was reduced by from June to July
= ²²⁰⁰₈₀₀₀ x 100%
= 27.5%

Answer(s): 27.5%