Question

急，急，急！

Answer 1

2/9-7/10×2/9
=2/9×(1-7/10)
=2/9×3/10
=1/15

追问

错了

题目都弄错了，

追答

16?

2/9-7/16×2/9
=2/9×(1-7/16)
=2/9×3/16
=1/24。

ok？

2/9-7/16×2/9
=2/9×(1-7/16)
=2/9×9/16
=1/8。