=5/14x9/11+13/14x5/11
=5/11x9/14+5/11x13/14
=5/11x(9/14+13/14)
=5/11x22/14
=5/11x11/7
=5/7
希望能帮你忙,懂了请采纳,
还有四分之三×五分之一加四分之三乘五分之二加0.75乘五分之三减四分之三
=3/4x1/5+3/4x2/5+0.75x3/5-3/4
=3/4x(1/5+2/5+3/5-1)
=3/4x1/5
=3/20