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If the sum of five consecutive even integers is 70, what is the value of the greatest of the five integers.
A.12
B.14
C.18
D.20
E.22

A.A.12
B.14
C.18
D.20

【参考答案】

C
解析:若5个连续偶数(consecutive even integer)的和为70,则5个数中数值最大的数是多少?
解:本题的正确答案为(C)。5个连续偶数构成了一个公差等于2的等差数列。对于等差数列有如下性质:[*]。对这5个连续偶数应用此公式可得:a1+a5=a2+a4=2a...

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