Question

帮个忙呗

Answer 1

1/4×（39+1）=10

追答

第二题按顺序计算

第三题（8/13+5/13）×1/7=1/7

第四题4/9 ×（4/5-1/5－1/3）

追问

等于多少

追答

5/3 请采纳

Answer 2

1/4X39+1/4
=39/4+1/4
=40/4
=10

追问

第2道题

追答

8/9×3/8÷1/27
=1/3×27
=9

8/13÷7+1/7×5/13
=8/13×1/7+1/7x5/13
=1/7×(8/13+5/13)
=1/7×1
=1/7

4/9÷[4/5-(1/5+1/3)]
=4/9÷[4/5-1/5-1/3]
=4/9÷[9/15-5/15]
=4/9÷4/15
=4/9x15/4
=5/3