(7/15+7/30+4/5)+(2-1/3-1/2) (1/6+1/10+1/15): (3/5-1/3-1/4

(7/15+7/30+4/5)+(2-1/3-1/2) = (14/30 + 7/30 + 24/30) + (12/6 - 2/6 - 3/6) = 45/30 + 7/6 = 45/30 + 35/30 = 80/30  =  = 

(1/6+1/10+1/15):(3/5-1/3-1/4) = (5/30 + 3/30 + 2/30) : (36/60 - 20/60 - 15/60) = 10/30 * 60 = 20 

Забыл про второе :з