We have the proportion: \[ \frac{a}{3} = \frac{24}{9} \] Simplify the ratio \( \frac{24}{9} = \frac{8}{3} \), so we get: \[ \frac{a}{3} = \frac{8}{3} \] Cross-multiply to solve for \( a \): \[ a = 8 \] To solve ratios, cross-multiply the values and solve for the unknown variable.