1 2/9 : 3 2/3 + 4 2/5 : (7/10 + 2 3/5) - (3/17 - 1 16/17 : 11) = 11/9 : 11/3 + 22/5 : (7/10 + 13/5) - (3/17 + 33/17 : 11/1) = 11/9 * 3/11 + 22/5 : (7+26)/10 - (3/17 + 33/17 * 1/11) = 1/3 + 22/5 : 33/10 - (3/17 + 3/17) = 1/3 + 22/5 * 10/33 - 6/17 = 1/3 + 4/3 - 6/17 = (51+204-18)/51 = 237/51 = 4 33/51 = 4 11/17