Question

速度回答!一题5分!要详细的过程!

Answer 1

你分数的分子分母写反了吧?

8/5,应该是5/8（8分之5吧）其他的也这样

1.

(5/8+5/6）×4/25

=5/8×4/25+5/6×4/25

=1/10+2/15

=3/30+4/30

=7/30

2.

（5/6-2/3）×9/10

=（5/6-4/6）×9/10

=1/6×9/10

=3/20

3.

1-7/9÷7/8

=1-7/9×8/7

=1-8/9

=1/9