=(28/5)*(9/4)+(22/5)*(9/4)
=(28/5+22/5)*(9/4)
=(50/5)/(9/4)
=10*9/4
=90/4
=22.5



=5.6*(9/4)+(44/10)*(9/4)
=(5.6+4.4)*(9/4)
=90/4
=22.5好难呀有木有简单一点的啦~\(≧▽≦)/~