(6 1/8 - 1 3/4) : (9 - 2 1/5 * (5 6/11 - 3 1/2)) * 1 2/7 = (49/8 - 7/4) : (9 - 11/5 * (61/11 - 7/2)) * 9/7 = (49-14)/8 : (9 - 11/5 * (122-77)22) * 9/7 = 35/8 : (9 - 11/5 * 45/22) * 9/7 = 35/8 : (9 - 9/2) * 9/7 = 35/8 : (18-9)/2 * 9/7 = 35/8 : 9/2 * 9/7 = 35/8 * 2/9 * 9/7 = 35/36 * 9/7 = 5/4 = 1 1/4
(3 5/6 - 1 2/15) * 5/9 + ((1/20 + 24/100) * 8 1/3 - 1 1/6) * 2 = (23/6 - 17/15) * 5/9 + ((5+24)/100 * 25/3 - 7/6) * 2 = (230-68)/60 * 5/9 + (29/100 * 25/3 - 7/6) * 2 = 162/60 * 5/9 + (29/12 - 7/6) * 2 = 18/12 + (29-14)/12 * 2 = 18/12 + 15/12 * 2 = 18/12 + 15/6 = (18+30)/12 = 48/12 = 4