In the grid below, $\frac{4}{28}$428 parts have been shaded. Use the grid to simplify $\frac{4}{28}$428.
In the grid below, $\frac{20}{32}$2032 parts have been shaded. Use the grid to simplify $\frac{20}{32}$2032.
In the grid below, $\frac{12}{24}$1224 parts have been shaded. Use the grid to simplify $\frac{12}{24}$1224.
Simplify the fraction $\frac{3}{9}$39.