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题库 / Prep2007E2-DS-10
Juan bought some paperback books that cost $8 each and some hardcover books that cost $25 each. If Juan bought more than 10 paperback books, how many hardcover books did he buy?
(1) The total cost of the hardcover books that Juan bought was at least $150.
(2) The total cost of all the books that Juan bought was less than $260.
Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.
Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient.
BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.
EACH statement ALONE is sufficient.
Statements (1) and (2) TOGETHER are NOT sufficient.
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2) less than
题目：当纸质more than 10本（意味着x>10又因为x,y 都为整数，则有x>=11）求y的值。
条件一：25y≥150 即 y≥6
条件二：8x+25y
注意问的是hardcopy的值。。。。p确实可以＝11，12，13 但是hardcopy只能6，取到7就超了登录 或 注册 后可以参加讨论