In April, Xavier gave his wife, Lynn, $4500 for household expenditure. Lynn spent 50% of the sum on rental, 20% on food and saved the rest. In May, Xavier reduced the sum he gave to Lynn. Lynn spent the same amount on rental and reduced the amount she spent on food by 30%. She saved the remaining 20% of the sum given to her in May. By what percentage was the sum given to Lynn reduced by?

	Rental	Food	Savings	Total
Before	50%	20%	30%	$4500
Change		- 6%	- ?	- ?
After	50%	14%
Comparing the amounts spent in May	80 u		20 u	100 u

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

Amount that Xavier reduced on food in percent
= 30% x 20%
= ³⁰₁₀₀ x 20
= 6%

Total amount that Xavier spent on rental and food in percent
= 50% + 14%
= 64%

100% → 4500

1% → 4500 ÷ 100 = 45

64% → 64 x  45 = 2880

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

80 u = 64% 

80 u = 2880

1 u = 2880 ÷ 80 = 36

Amount that Xavier gave to Lynn in May
= 100 u
= 100 x 36
= $3600

Amount that Lynn received less from Xavier from April to May
= 4500 - 3600
= $900

Percentage that the sum given to Lynn was reduced by from April to May
= ⁹⁰⁰₄₅₀₀ x 100%
= 20%

Answer(s): 20%