П.4 Вычислите: 1) 11 · 1 17/55 - 15,3; 2) 3 4/7 · 4,5 · 7/35 · 8,75 : 2/5 : 9/32; 3) 19 · 2 55/76 - 39,4; 4) 6,8 · 5/13 · 2,7 · 3/25 : 5/2 · 1/175

1. 11 * (72/55) - 15.3 = 792/55 - 15.3 = 14.4 - 15.3 = -0.9. 2. (25/7) * (9/2) * (7/35) * (35/4) * (5/2) * (32/9) = (25*9*7*35*5*32) / (7*2*35*4*2*9) = (25*5*32) / (2*4*2) = (25*5*32) / 16 = 25*5*2 = 250. 3. 19 * (154+55)/76 - 39.4 = 19 * (209/76) - 39.4 = 19 * (11*19)/(4*19) - 39.4 = 19 * 11/4 - 39.4 = 209/4 - 39.4 = 52.25 - 39.4 = 12.85. 4. (68/10) * (5/13) * (27/10) * (3/25) * (2/5) * (1/175) = (34/5) * (5/13) * (27/10) * (3/25) * (2/5) * (1/175) = (34/13) * (27/10) * (3/25) * (2/5) * (1/175) = (34*27*3*2) / (13*10*25*5*175) = 54432 / 5656250 = 0.009623... (approx.)