9又3/4-15除以19-2/19*2 =39/4-15/19-2/19*2=39/4-1=35/4=8又4分之3 (4/19*2.532+1.768*4/19)+4.3除以1又4/15=4/19*（2.532+1.768）+4.3÷19/15=4/19*4.3+4.3*15/19=4.3*(4/19+15/19)=4.3
