A truck travels at a speed of 60 km/h from city P to city Q and returns to city P by the same route at a speed of 100 km/h. What is the average speed of the truck for the given journey?

Correct option is D

Given:

The speed of truck P to Q = 60 km/h 

The speed of truck Q to P = 100 km/h 

Formula Used:

Average speed = $$\frac{2v_1v_2}{v_1 +v_2}$$ 

Solution:

= $$\frac{2\times60\times100}{60+100}$$ 

                      = 75 km/h 

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