题目内容
2+4=2×3 2+4+6=3×4 2+4+6+8=4×5 2+4+6+8+…+100=
50
50
×51
51
．分析：从2+4=2×3 2+4+6=3×4 2+4+6+8=4×5，可以看出：算式等号左边都是连续的偶数，右边的结果为：偶数的个数×（个数+1），即n×（n+1），据此解答．
解答：解：算式2+4+6+8+…+100有50个偶数相加，根据以上分析，可得：
2+4+6+8+…+100=50×51；
故答案为：50，51．
2+4+6+8+…+100=50×51；
故答案为：50，51．
点评：观察特例特点，找出规律，根据规律进行解答．
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