2分之1加4分之1加8分之1加16分之1加64分之1加128分之1加256分之1 等于几?过程也写出来.

1/2+1/4+1/8+1/16+1/64+1/128+1/256
=(1/2+1/4)+(1/8+1/16)+(1/64+1/128)+1/256
=(2/4+1/4)+(2/16+1/16)+(2/128+1/128)+1/256
=3/4+3/16+3/128+1/256
=(3/4+3/16)+(3/128+1/256)
=(12/16+3/16)+(6/256+1/256)
=15/16+7/256
=240/256+7/256
=247/256