3. 9/14:(1. 3/7-5/21*0,9)-0,76
3 9/14 : (1 3/7 - 5/21 * 0,9) - 0,76 = 2,24 1) 5/21 * 0,9 = 5/21 * 9/10 = (1*3)/(7*2) = 3/14 2) 1 3/7 - 3/14 = 1 6/14 - 3/14 = 1 3/14 3) 3 9/14 : 1 3/14 = 51/14 : 17/14 = 51/14 * 14/17 = 51/17 = 3 4) 3 - 0,76 = 2,2