1 4 6 5 2 3 7
((3 1/3 + 5 7/9 ) * 2 1/4 - 11/15 * (3 5/6 - 7/12 + 9 7/8)) * 16/39 =
= 4 6/13
1) 3 1/3 + 5 7/9 = 3 3/9 + 5 7/9 = 9 1/9
2) 3 5/6 - 7/12 = 3 10/12 - 7/12 = 3 3/12 = 3 1/4
3) 3 1/4 + 9 7/8 = 3 2/8 + 9 7/8 = 13 1/8
4) 9 1/9 * 2 1/4 = 82/9 * 9/4 = 82/4 = 41/2 = 20 1/2
5) 11/15 * 13 1/8 = 11/15 * 105/8 = (11*7)/(1*8) = 77/8 = 9 5/8
6) 20 1/2 - 9 5/8 = 20 4/8 - 9 5/8 = 10 7/8
7) 10 7/8 * 16/39 = 87/8 * 16/39 = (29 *2)/ (1*13) = 58/13 = 4 6/13