(0,9-1/3+0,75-1/15)0,5-1/6):5/12 = (9/10-1/3+3/4-1/15)1/2-1/6) * 12/5 = (27-10+7.5-2)/30 3-1) /6 * 12/5 = 22.5 /30 : 2 /6 * 12/5 = 22.5 /30 * 6/2 * 12/5 = (22.5*6*12) / (30*2*5) = (22.5*6*12) / (30*2*5) = 1620 / 300= = 5,4