• # question_answer 10)                 A loaded truck travels 14 km in 25 minutes. If the speed remains the same, how far can it travel in 5 hours?

Two quantities $x$ and $y$ which vary in direct proportion have the relation $x=ky$               or  $\frac{x}{y}=k$                        Here, $k=\frac{\text{number}\,\text{of}\,\text{km}\,\,\text{it}\,\text{can}\,\text{travel}}{\text{time}\,\text{in}\,\text{hours}}$ $=\frac{14}{\left( \frac{25}{60} \right)}=\frac{14\times 60}{25}$ $=\frac{168}{5}$ Now, $x$ is the distance travelled in 5 hours Using the relation $x=ky,$ we obtain $x=\frac{168}{5}\times 5$ $\Rightarrow$               $x=168$ Hence, it can travel 168 km.