задание 1):
1)
3 1/4 + 0,25 - 1 5/24 = (3 - 1) + (1/4 + 25/100 - 5/24) =
= 2 + (1/4 + 1/4 - 5/24) = 2 + (12/24 - 5/24) = 2 7/24,
2)
2 3/4 - 4 1/2 - 0,75 = (2 - 4) + (3/4 - 1/2 - 75/100) =
= -2 + (3/4 - 1/2 - 3/4) = -2 - 1/2 = - (2 + 1/2) = - 2 1/2,
3)
2 7/24 : (-2 1/2) = 55/24 : (-5/2) = 55/24 * (-2/5) = -11/12,
4)
-11/12 : (-4 7/12) = -11/12 : (-55/12) = 11/12 * 12/55 = 11/55 = 1/5 (или 0,2)
