29×二十八分之二十七+27×(1+1/28)
=27×29/28+27×29/28
=2×27×29/28
=2×(28-1)×(28+1)/28
=2×28-2/28
=56-1/14
=55又13/14
29×二十八分之二十七+27×(1+1/28)
29×二十八分之二十七+27×(1+1/28)
=27×29/28+27×29/28
=2×27×29/28
=2×(28-1)×(28+1)/28
=2×28-2/28
=56-1/14
=55又13/14