问题
单项选择题
On the day of the performance of a certain play, each ticket that regularly sells for less than$10,00 is sold for half price plus $0.50, and each ticket that regularly sells for$10.00 or more is sold for half price plus$1.00. On the day of the performance, a person purchases a total of y tickets, of which x regularly sell for $9.00 each and the rest regularly sell for $12.00 each. What is the amount paid, in dollars, for the y tickets ？（）
A.7y-2x
B.12x-7y
C.
D.7y+4x
E.7y+5x
答案
参考答案：A
解析：
根据题意可知x张通常售价为9美元的票得付[*]美元；y-x张通常票价为12美元的票得付的钱为[*]。所以此人总共为票付了5x+7(y-x)=7y-2x。