In this section, students add and subtract fractions and mixed numbers with unlike denominators, and apply this learning to problem solving. Students first encounter problems where one denominator is a factor of the other (for example, \(\frac {1}{4}\)s and \(\frac {1}{8}\)s), so that they will only need to change one denominator. Then, students solve problems where the denominators are not related (for example, \(\frac {1}{3}\)s and \(\frac {1}{4}\)s). Students conclude that multiplying the denominators or finding a common multiple are helpful ways to create common denominators.

5.6 Family Support Material