Explanation: A mixed number is formed by combining three parts: a whole number, a numerator, and a denominator. The numerator and denominator are part of the proper fraction that makes the mixed number. Properties of mixed numbers. It is partly a whole number. It is partly a fraction. 1. Find the whole number. 17/2 gives 8.5, 8 is the whole number 2.Find the fraction. 8.5 has a .5 decimal which is equivalent to 1/2 3.Combine. 8+1/2 is 8 and 1/2 or 8.5