Compute the cross products: $\displaystyle{10}\cdot{40}={400}\usepackage{cmbright}\Huge\$ and $\displaystyle{16}\cdot{25}={400}\usepackage{cmbright}\Huge\$ . Because the products are equal, the proportion is true. The question asked which proportion is false. The proportion $\displaystyle\frac{{14}}{{35}}=\frac{{35}}{{70}}\usepackage{cmbright}\Huge\$ is false, so it is the correct answer.