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いちろーです。
いつもお世話になります。
下記の2問教えてください。
１．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 performances, 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) (9x + 12y)/2
(D) 7y + 4x
(E) 7y + 5x
正解は（Ａ）です。
どのように立式したらよいのか分かりません。
２．If a person purchases 15 of the 3,000 tickets sold in a raffle that awards one prize, what is the probability that this person will not win?
(A) 0
(B) 1/200
(C) 1/2
(D) 199/200
(E) 1
正解は（Ｄ）です。
答えから推測すると、3000ticketsのうち、15がwinという意味なのでしょうか？
特に15 of the 3,000 tickets と that awards one prize のつながりがよく分かりません。
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