(7/15+7/30+4/5) : (2-1/3-1/2) . вычислите

1)7/15 + 7/30 +4/5 = 14/30 + 7/30 + 24/30 = 45/30 = 1 15/30 = 1 1/2 2) 2 - 1/3 - 1/2 = 12/6 - 2/6 - 3/6 = 7/6 = 1 1/6 3) 1 1/2 : 1 1/6 = 3/2 : 7/6 = 9/7 = 1 2/7