(3x^(-1/2)*3x^(1/2)y^(-1/3))/(3y^(-7/4)
:.=(9x^(-1/2+1/2)*y^(-1/3))/(3y^(-7/4))
:.=(cancel9^color(blue)3x^0*y^(-1/3))/(cancel3^color(blue)1y^(-7/4))
:.=(3*1*y^(-1/3))/y^(-7/4)
:.=3/y^(-7/4+1/3)
:.=color(blue)(3/(y^(-17/12) color(white)(aaaaaaaaaaaaa) -7/4+1/3=(-21+4)/12=color(blue)(-17/12