AMC 8 1992 Problem 7

AMC8 1992 年第 7 题

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The digit-sum of 998 is 9+9+8=26 . How many 3-digit whole numbers, whose digit-sum is 26 , are even?

998 的各位数字之和是 9+9+8=26。有多少个三位正整数，其各位数字之和为 26，且为偶数？

正确答案 · Correct Answer

解析 · Solution

Solution 1

The highest digit sum for three-digit numbers is 9+9+9=27. Therefore, the only possible digit combination is 9, 9, 8. Of course, of the three possible numbers, only 998 works. Thus, the answer is

\text{(A)1}

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