(4,25 * 16/51 - 17/18 : 8,5) * (3/11)^2 = 1/11
1) 4,25 * 16/51 = 425/100 * 16/51 = (25*4)/(25*3) = 4/3 = 1 1/3
2) 17/18 : 8,5 = 17/18 : 85/10 = 17/18 * 10/85 = (1*5)/(9*5) = 1/9
3) 1 1/3 - 1/9 = 1 3/9 - 1/9 = 1 2/9
4) (3/11)^2 = 3/11 * 3/11 = 9/121
5) 1 2/9 * 9/121 = 11/9 * 9/121 = 11/121 = 1/11