At a certain restaurant, if each hamburger costs the same amount, whatis the cost, excluding sales tax, of 1 hamburger?
(1) The total cost, including a 6 percent salestax, is $4.77 for 3 hamburgers.
(2) The total cost, including a 6 percent salestax, is less than $6.50 for 4 hamburgers.
答案是A,解释如下:
【思路】設hamburger成本=h, 問 h=?
(1) 3h(0.06) = 4.77,可得h,充分
(2) 4h(0.06) < 6.50 ,不知h多少,不充分
我觉得答案有问题,因为我对题目中的概念理解与答案不同。
首先我觉得sales tax的征税基础应该是售价price;其次,cost不等于price;
所以(1)应为4.77=3(6%price+ex-tax cost); (2)同理也是含有2个变量,所以E