Question

一减六分之一加四十二分之一加五十六分之一加七十二分之一的答案？

怎么样算

Answer 1

1-1/6+1/42+1/56+1/72
=6/6-1/6+1/42+1/56+1/72
5/6+1/42+1/56+1/72
=35/42+1/42+1/56+1/72
=36/42+1/56+1/72
1/7*（36/6+1/8）+1/72
=1/7（6+1/8）+1/72
=1/7（48/8+1/8）+1/72
=1/7（49/8）+1/72
=49/56+1/72
=49/7*8+1/8*9
=1/8*（49/7+1/9）
=1/8*（7+1/9）
=1/8*（63/9+1/9）
=1/8*64/9
=64/72
=8/9