4/45-1/30 помогите решить
4/45 - 1/30 = (4 × 2 - 1 × 3)/90 = 8/90 - 3/90 = 5/90 = 1/18
4/45-1/30=4/(3*15)-1/(2*15)=(4*2)/(3*15*2)-(1*3)/(2*15*3)=8/90-3/90=5/90=1/18