配套习题- 优先考虑排列组合中的特殊元素 -【青果学院】

1/3单选题

难度：

1.用0,1,2,3,组成没有重复数字的四位数其中偶数有__________个。

A	8
B	10
C	5
D	6

正确答案：Qg==

6Kej77ya6L+Z6YeMMOaYr+eJueauiueahOWFg+e0oO+8jDDkuI3og73lnKjljYPkvY3jgILlvZPmnKvlsL7mlbDlrZfmmK8w55qE5pe25YCZ77yM5Ymp5L2Z55qEM+S4quWFg+e0oOWFqOaOkuWIl++8jOatpOaXtuaciTxpbWcgd2lkdGg9NDEgaGVpZ2h0PTIxIHNyYz0iaHR0cHM6Ly9wMi5xaW5nZ3VvLmNvbS9HMS9NMDAvNEMvRkUvckJBQ0UxTjE3XzNTWVROQ0FBQUJxckFnRXo0ODA3LnBuZyI+5Liq5YG25pWw77yM5aaC5p6cMuWcqOacq+WwvuaVsO+8jOmCo+S5iDDmnIky56eN6YCJ5oup77yM5Ymp5L2Z55qE5Lik5Liq5pWw5pyJMuenjemAieaLqe+8jOi/meenjeaDheWGteS4i++8jOaciTTkuKrlgbbmlbDjgILlhbHmnIk2KzQ9MTDkuKrlgbbmlbDjgII=

2/3单选题

难度：

2.7种不同的花种在排成一排的7个花盆里，有两种葵花不种在中间也不种在两端，有______种不同的种法。

A	1440
B	1223
C	920
D	261

正确答案：QQ==

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

3/3单选题

难度：

3.用0,1,2,3,4,这5个数组成没有重复数字的三位数，其中偶数有___________个。

A	20
B	30
C	40
D	50

正确答案：Qg==

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