Of the total amount that Jill spent on a shopping trip, excluding taxes, she spent 50 percent on clothing, 20 percent on food, and 30 percent on other items. If Jill paid a 4 percent tax on the clothing, no tax on the food, and an 8 percent tax on all other items, then the total tax that she paid was what percent of the total amount that she spent, excluding taxes?

A. 2.8%

B. 3.6%

C. 4.4%

D. 5.2%

E. 6.0%

设不含税的收入为x,则(x*0.5*0.04+x*0.3*0.08)/x+(x*0.5*0.04+x*0.3*0.08)=4.12%.请问这样算对吗