Сколько будет 4*2/7-3*2/9-5*5/7 ?
1) 4/1 * 2/7 = 8/7 = 1 целая 1/7 2) 3 * 2/9 = 3/1 * 2/9 = 2/3 3) 5 * 5/7 = 5/1 * 5/7 = 25/7 = 3 целых 4/7 4) 1 целая 1/7 - 2/3 = 1 целая 3/21 - 14/21 = 10/21 5) 10/21 - 3 целых 4/7 = 10/21 - 3 целых 12/21 = -2 целых 2/21