А) (2 2/9 - 1 5/6)*(4/7 + 1/2)
Решаем по действиям.
1) 2 2/9 - 1 5/6 = 20/9 - 11/6 = 40/18 - 33/18 = 7/18
2) 4/7 + 1/2 = 8/14 + 7/14 = 15/14
3) 7/18*15/14 = 7/14*15/18 = 1/2*5/6 = 5/12
Б) (1 4/5 + 2/5)*(1/2 + 3/4)
Решаем по действиям.
1) 1 4/5 + 2/5 = 9/5 + 2/5 = 11/5
2) 1/2 + 3/4 = 2/4 + 3/4 = 5/4
3) 11/5*5/4 = 11/4 = 2 3/4 = 2,75