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标题: GMAT Mahattan 上一题 [打印本页]

作者: xiuxiuxixi 时间: 2013-3-17 14:20
标题: GMAT Mahattan 上一题
1 How many three-digit numbers begin with a digit which represents an odd number that is a prime, have a prime number as a second digit, and end with a digit that represents an odd number?
?   A15
?   B60
?   C75
?   D80
?   E100

作者: hujiagz 时间: 2013-3-17 20:49

1 How many three-digit numbers begin with a digit which represents an odd number that is a prime, have a prime number as a second digit, and end with a digit that represents an odd number?
? A15
? B60
? C75
? D80
? E100

-- by 会员 xiuxiuxixi (2013/3/17 14:20:08)

我觉得是B，
10以内的Prime number有2， 3， 5， 7，奇数有1， 3， 5， 7， 9
百位有3种可能，十位有4种可能，个位有5种可能，所以结果应该是3*4*5=60.

作者: xiuxiuxixi 时间: 2013-3-18 08:47
感谢不好意思忘记附答案了答案就是B

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