简便计算 1+1/3-7/12+9/20-11/30+13/42-15/56

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简便计算 1+1/3-7/12+9/20-11/30+13/42-15/56

简便计算 1+1/3-7/12+9/20-11/30+13/42-15/56
简便计算 1+1/3-7/12+9/20-11/30+13/42-15/56

简便计算 1+1/3-7/12+9/20-11/30+13/42-15/56
1+1/3-7/12+9/20-11/30+13/42-15/56
=1+1/3-1/3-1/4+1/4+1/5-1/5-1/6+1/6+1/7-1/7-1/8
=1-1/8
=7/8

1+1/3-7/12+9/20-11/30+13/42-15/56
=1+1/3-(1/3+1/4)+(1/4+1/5)-(1/5+1/6)+(1/6+1/7)-(1/7+1/8)
=1-1/8
=7/8

1+1/3-7/12+9/20-11/30+13/42-15/56
=1+1/3-(1/3+1/4)+(1/4+1/5)-(1/5+1/6)+(1/6+1/7)-(1/7+1/8)
=1+1/3-1/3-1/4+1/4+1/5-1/5-1/6+1/6+1/7-1/7-1/8
=1-1/8
=7/8

1+1/3-7/12+9/20-11/30+13/42-15/56
=4/3-7/3+7/4+9/4-9/5-11/5+11/6+13/6-13/7-15/7+15/8
=-1+4-4+4-4+15/8
=7/8

{1/3*16/4-1/3*7/4}+{1/2*27/30-1/2*22/30}+{1/7*52/24-1/7*45/24}
=3/4+1/12+1/24
=(18+2+1)/24
=7/8

1+1/3-7/12+9/20-11/30+13/42-15/56
=1+1/3-1/3-1/4+1/4+1/5-1/5-1/6+1/6+1/7-1/7-1/8
=1-1/8
=7/8