9/20÷[1/2×(2/5+4/5)]简算

问题描述:

9/20÷[1/2×(2/5+4/5)]简算

9/20÷[1/2×(2/5+4/5)]
=9/20÷[1/2×(6/5)]
=9/20÷(3/5)
=3/4