(3 1/2-2 2/3+5 5/6+4 3/5)*1 2/13=
(3 1/2 - 2 2/3 + 5 5/6 + 4 3/5) * 1 2/13 = 13 1) 3 1/2 - 2 2/3 = 3 3/6 - 2 4/6 = 2 9/6 - 2 4/6 = 5/6 2) 5/6 + 5 5/6 = 5 10/6 = 6 4/6 = 6 2/3 3) 6 2/3 + 4 3/5 = 6 10/15 + 4 9/15 = 10 19/15 = 11 4/15 4) 11 4/15 * 1 2/13 = 169/15 * 15/13 = 169/13 = 13
(31/2-2 2/3 + 5 5/6 + 4 3/5) * 1 2/13 31/2 - 2 2/3 = 77/6 77/6 + 35/6 = 112/6. 35/6 = 5 5/6 112/6 + 23/5 = 116/5. 23/5 = 4 3/5 116/5 * 15/13 = 26 10/14