вычислите : ( (1/4-1/12)*5=? д). (1/4+1/6): 10=? е). (5/6-1/4): 7=?

(1/4-1/12)*5=( (3-1)/12)*5= 2/12*5=1/6*5=5/6
(1/4+1/6):10= ((3+2)/12):10=5/12:10/1=5/12*1/10=1/12*2=1/24
(5/6-1/4):7=((10-3)/12):7=7/12:7/1=7/12*1/7=1/12