In January, Brandon gave his wife, Nicole, $4000 for household expenditure. Nicole spent 70% of the sum on rental, 10% on food and saved the rest. In February, Brandon reduced the sum he gave to Nicole. Nicole 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 February. By what percentage was the sum given to Nicole reduced by?

	Rental	Food	Savings	Total
Before	70%	10%	20%	$4000
Change		- 2%	- ?	- ?
After	70%	8%
Comparing the amounts spent in February	80 u		20 u	100 u

Amount that Brandon saved in percent
= 100% - 70% - 10%
= 20%

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

Total amount that Brandon spent on rental and food in percent
= 70% + 8%
= 78%

100% → 4000

1% → 4000 ÷ 100 = 40

78% → 78 x  40 = 3120

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

80 u = 78% 

80 u = 3120

1 u = 3120 ÷ 80 = 39

Amount that Brandon gave to Nicole in February
= 100 u
= 100 x 39
= $3900

Amount that Nicole received less from Brandon from January to February
= 4000 - 3900
= $100

Percentage that the sum given to Nicole was reduced by from January to February
= ¹⁰⁰₄₀₀₀ x 100%
= 2.5%

Answer(s): 2.5%