put a 1 under the 13, so it is 13/1, and 5 5/6, turn it into an improper fraction by multiplying 5x6=30. then 30+5, which is 35. so just keep the denominator, which would be 35/6. so you would have 13/1 - 35/6. you need the same denominator, so see what both 1 and 6 would fit into. which is 6. so 13x6 which is 78, so 78/6 - 35/6, so 78-35 is 43. so 43/6, then simplify, which is 7 1/6