2 1/2 * 6 + 3 1/3 = 18 1/3
1) 2 1/2 * 6 = 5/2 * 6 = 15
2) 15 + 3 1/3 = 14 3/3 + 3 1/3 = 17 4/3 = 18 1/3
2 1/2 * 2 + 3 1/3 * 3 = 15
1) 2 1/2 * 2 = 5/2 * 2 = 5
2) 3 1/3 * 3 = 10/3 * 3 = 10
3) 5 + 10 = 15
17 : (4 1/3 - 3 1/5) = 15
1) 4 1/3 - 3 1/5 = 13/3 - 16/5 = (5*13 - 3*16)/15 = (65 - 48)/15 = 17/15
2) 17 : 17/15 = 17 * 15/17 = 15