Снизу 4 плизззззззззззззз
=(31/30 - 13/5 -4/30 + 6/1) -(7/1 - 83/12 + 1/4) = (31/30 - 78/30 - 4/30 +180/30) - (84/12 - 83/12 + 3/12) = 129/30 - 4/12 = 43/10 - 1/3 =129/30 - 10/30=119/30 = 3ц29/30