Calculate the speed of a motor vehicle after it took 2 minutes to travel 2.4 km.

The distance traveled is $2.4 \text{ km}$.
The time taken is $2 \text{ minutes}$.
The formula for speed is:

$$\text{Speed} = \frac{\text{Distance}}{\text{Time}}$$

Since there are $60 \text{ minutes}$ in $1 \text{ hour}$:

$$\text{Time in hours} = \frac{2 \text{ minutes}}{60 \text{ minutes/hour}}$$ $$\text{Time in hours} = \frac{1}{30} \text{ hours}$$

Substitute the distance and time (in hours) into the speed formula:

$$\text{Speed} = \frac{2.4 \text{ km}}{\frac{1}{30} \text{ hours}}$$ $$\text{Speed} = 2.4 \times 30 \text{ km/h}$$ $$\text{Speed} = 72 \text{ km/h}$$

The speed of the motor vehicle is $72 \text{ km/h}$.