Which fraction equals 12\frac{1}{2}?
Multiply or divide both numbers by the same nonzero number to keep the same amount: 12=24=48\frac{1}{2} = \frac{2}{4} = \frac{4}{8}.
What completes 25=?15\frac{2}{5} = \frac{?}{15}?
Sam says 25=47\frac{2}{5} = \frac{4}{7}. What should change?