Question

列式计算，过程详细！@！！！

13/17-12/7-13/5 7.2×1.25÷7.2×8 72.56-（12.56-7.98）
= = =
= = =
= = =
113.27-（59.4+13.27） X-4/3=9/1 1/2+1/6+1/12+1/20+1/30
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= = =
1/2×3+1/3×4+1/4×5+1/5×6+1/6×7
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Answer 1

最后一道=1/2-1/3+1/3-1/4+1/4-1/5+1/5-1/6+1/6-1/7=1/2-1/7=5/14

追问

前面不是还有好几道吗，怎么才回答了一道，不好意思等于号打在一起了

追答

前面两道式子你没打清楚13/5 7.2×1.25
还有（59.4+13.27） X-4/3=9/1 1/2

追问

还有这个1/2+1/6+1/12+1/20+1/30

7.2×1.25÷7.2×8这是第二道

追答

13/17-12/7-13/5 用通分解
7.2×1.25÷7.2×8将小数化为分数
72.56-（12.56-7.98） 去括号

113.27-（59.4+13.27）去括号
X-4/3=9/1 一元一次方程
1/2+1/6+1/12+1/20+1/30 和最后一题同样的思想