5⼀7-5⼀9×5⼀7。1-5⼀7×21⼀25。,1⼀2+5⼀4×4⼀5。1⼀6×5-2⼀3。7⼀

2025-03-23 11:55:19
推荐回答(1个)
回答1:

5/7-5/9×5/7
=5/7×(1-5/9)
=5/7×4/9
=20/63

1-5/7×21/25
=1-3/5
=2/5

1/2+5/4×4/5
=1/2+1
=1又1/2

1/6×5-2/3
=5/6-2/3
=1/6

7/8×7+7/8

=7/8×(7+1)
=7/8×8
=7