Question

A large box of nails weighed 3 1 ⁄8 ounces. A small box of nails weighed 2 4 ⁄8 ounces. What is the difference in weight between the two boxes?

Answer 1

let's firstly convert the mixed fractions to improper fractions and then get their difference

$\stackrel{mixed}{3\frac{1}{8}}\implies \cfrac{3\cdot 8+1}{8}\implies \stackrel{improper}{\cfrac{25}{8}}~\hfill \stackrel{mixed}{2\frac{4}{8}}\implies \cfrac{2\cdot 8+4}{8}\implies \stackrel{improper}{\cfrac{20}{8}} \\\\[-0.35em] ~\dotfill\\\\ \cfrac{25}{8}-\cfrac{20}{8}\implies \cfrac{25-20}{8}\implies \cfrac{5}{8}~oz$