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1/2×3+1/3×4+1/4×5+1/5×6+1/6×7+1/7×8.求简便方法啊

题目详情
1/2×3+1/3×4+1/4×5+1/5×6+1/6×7+1/7×8.求简便方法啊
▼优质解答
答案和解析
1/2×3+1/3×4+1/4×5+1/5×6+1/6×7+1/7×8
=1/2-1/3+1/3-1/4+1/4-1/5+1/5-1/6+1/6-1/7+1/7-1/8
=1/2-1/8
=3/8