参考答案：B
【解析】原式=1/(6*7)+1/(7*8)+1/(8*9)+1/(9*10)+1/(10*11)=1/6-1/7+1/7-1/8+1/8-1/9+1/9-1/10+1/10-1/11=1/6-1/11=5/66。故答案为B
河南试题资料
1/42+1/56+1/72+1/90+1/110的值是A. 1/6B. 5/66C. 7/85D. 11/128
华图教育 | 2020-04-06 20:03
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河南试题资料
1/42+1/56+1/72+1/90+1/110的值是A. 1/6B. 5/66C. 7/85D. 11/128
华图教育 | 2020-04-06 20:03
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参考答案：B
【解析】原式=1/(6*7)+1/(7*8)+1/(8*9)+1/(9*10)+1/(10*11)=1/6-1/7+1/7-1/8+1/8-1/9+1/9-1/10+1/10-1/11=1/6-1/11=5/66。故答案为B
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