Question

(6 3/8 -2 3/4 )*(-4) + 7/18 * 9

Answer 1

(6 3/8 - 2 3/4) * (-4) + 7/18 * 9 = - 11

1) 6 3/8 - 2 3/4 = 6 3/8 - 2 6/8 = 5 11/8 - 2 6/8 = 3 5/8
2) 3 5/8 * (-4) = 29/8 * (-4) = - 29/2 = - 14 1/2 
3) 7/18 * 9 = 7/2 = 3 1/2
4) - 14 1/2 + 3 1/2 = - 11

Пояснения:
3/4 = (3*2)/(4*2) = 6/8 - доп.множ.2
3 5/8 = (3*8+5)/8 = 29/8