5又1/4:2又1/5=21/4:11/5=(21/4×20):(11/5×20)=105:44=105/44最简比是105:44,比值是105/44
5又1/4:2又1/5=21/4:11/5=21/4 x 5/11=105/44=105:44比值为105/44=2又17/44
5又1/4:2又1/5=105:44=2又17/44