Б) (2 7/15 + 1 7/12) * 1 1/9 - 1 7/8 в) (4 3/10 - 3 3/5*5/12) * 5/6 г) 4 1/3 - 3 4/9) 2 + (2 1/4) 2

Б)

(2 7/15 + 1 7/12) * 1 1/9 - 1 7/8 = (2 28/60 + 1 35/60) * 1 1/9 - 1 7/8 = 4 1/20 * 1 1/9 - 1 7/8 = 81/20 * 10/9 - 1 7/8 = 4 1/2 - 1 7/8 = 4 4/8 - 1 7/8 = 2 7/8.

в)

(4 3/10 - 3 3/5 * 5/12) * 5/6 = (4 3/10 - 18/5*5/12) * 5/6 = (4 3/10 - 1 1/2) * 5/6 = 2 4/5 * 5/6 = 14/5 * 5/6 = 2 1/3.

г) желательно пояснить выражение

Б) (2 7/15+1 7/12) * 11/9-1 7/8 = (37/15-19/12) * 11/9-15/8 = ((148+95) / 60) * 11/9-15/8 = (243*11) / (60*9) - 15/8 = (27*11) / 60 - 15/8 = (9*11) / 20 - 15/8 = 99/20-15/8 = (396-150) / 80 = 246/80=123/40 = 3 3/40

Г) (4 1/3 - 3 4/9) * 2 + (2 1/4) * 2 = (13/3-31/9) * 2+9/2 = ((39-31) / 9) * 2+9/2=8/9 * 2+9/2 = 16/9+9/2 = (32+81) / 18=113/18=6 5/18