Question

1 1/2- 5/6 +7/12 -9/20 +11/30 -13/42 +15/56

提示:1/2+1/3=5/6, 1/3=1/4=7/12,1/4+1/5=9/20……
帮忙解答一下!

Answer 1

原式=1+1/2-5/6+7/12-9/20+11/30-13/42+15/56=1+1/2-1/2-1/3
+(1/3+1/4)-1/4-1/5+(1/5+1/6)-1/6-1/7+(1/7+1/8)
=1+1/8=9/8

Answer 2

1/2+5/6−7/12+9/20−11/30+13/42−15/56等于多少？
1/2+5/6−7/12+9/20−11/30+13/42−15/56
=1/2+(3+2)/2×3−(4+3)/3×4+(5+4)/4×5−(6+5)/5×6+(7+6)/6×7−(8+7)/7×8
=1/2+1/2+1/3−1/3−1/4+1/4+1/5−1/5−1/6+1/6+1/7−1/7−1/8
=1/2+1/2−1/8
=7/8

Answer 3

1/2+5/6-7/12+9/20-11/30+13/42-15/56
=1-1/2+1/2+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

Answer 4

6分之5赋予2分之1加3分之1 , 后面一样念```

Answer 5

2楼正解~