Algebra 1: Common Core (15th Edition)

The 7 ounce part is already in ounces, so we do not have to worry about that yet. We first, however, need to put 4 pounds into ounces. Thus, we need to do a unit conversion in this problem. There are 16 ounces in a pound. Thus, we obtain: $\frac{4 pounds}{1} \times \frac{16 ounces}{pound} =64$ ounces. Note, we need to cancel out the unit of pounds, so we multiply 4 pounds by a fraction with pounds in the denominator. We add the additional 7 ounces to obtain a total of 71 ounces.