请教一道题，急，谢谢！！！

alankeepcalm

这题来自于新东方逻辑推理

One state adds a 7 percent sales tax to the price of most products purchased within its jurisdiction. This tax, therefore, if viewed as tax on income, has the reverse of the federal income tax: the lower the income, the higher the annual percentage rate at which the income is taxed.
The conculsion above would be properly drawn if which of the following were assumed as a premise?
A. The amount of money citizens spend on products subject to the state tax tends to be equal across income levels.
B. The federal income tax favors citizens with high incomes, whereas the state tax favors citizens with low incomes.
C. Citizens with low annual incomes can afford to pay a relatively higher percentage of their incomes in state sales tax, since their federal income tax is relatively low.
D.The lower a state's sales tax, the more it will tend to redistribute income from the more affluent citizens to the rest of society.
E. Citizens who fail to earn federal taxable income are also exempt from the state sales tax.


答案是A。有哪位大神可以帮我解答一下，万分感谢！

alzn2765

穷人：每个月花1000元买东西，占其收入的50％，这1000元收税7％，就是70元，税占收入的比例3.5%。
富人：每月个同样花1000元买东西，占其收入的5％，这1000元收税7％，就是70元，税占收入的比例0.35%。
是不是收入越高，实际缴税的比例越低？
求比例的初中数学题。。。。

alankeepcalm

alzn2765 发表于 2016-5-30 08:58
穷人：每个月花1000元买东西，占其收入的50％，这1000元收税7％，就是70元，税占收入的比例3.5%。
富人：每 ...

同意！