1/2+3/4+7/8+15/16+31/32+63/64+127/128=? 分数简便运算，急急急！

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等于（1-1/2）+（1-1/4）+（1-1/8）+（举春前1-1/16）森宴+（1-1/32）+（1-1/64）+（1-1/128）
=7-（1/正清2+1/4+1/8+1/16+1/32+1/64+1/128)
=7-127/128
=6又1/128

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=1-1/2+1-1/4+1-1/8+1-1/16+1-1/32+1-1/64+1-1/128
=7-(1/2+1/4+1/8+1/16+1/32+1/64+1/碰局128)
=7-(1/2+1/4+1/8+1/16+1/32+1/64+1/128+1/128)-1/128
=7+(1/2+1/4+1/8+1/16+1/32+1/64+1/64)-1/让改128)
=7+1-1/128
=7+127/坦吵判128

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