(7 целых 2/3 - 4 целых 4/15) - (1/4 + 1/5) + 1/20

15 целых 1/3 - (8 целых 1/2 + 1 целая 3/4 - 1 целая 2/5)

Ответ:

(7 2/3 - 4 4/15) - (1/4 + 1/5) + 1/20 = 3 2/5 - 9/20 = 2 19/20 = 2,95;

15 1/3 - (8 1/2 + 1 3/4 - 1 2/5) = 15 1/3 - (9 5/4 - 1 2/5) = 15 1/3 - 8 17/20 = 6 29/60