If a boat goes a certain distance at 30 km/hr and comes back the same distance at 60 km/hr. What is the average speed (in km/hr) for the total journey?
average speed = $$\frac{2ab}{a+b}=\frac{2(30)(60)}{30+60}=40$$
So the answer is option C.
Create a FREE account and get:
Quick, Easy and Effective Revision
By proceeding you agree to create your account
Free CAT Formulae PDF will be sent to your email address soon !!!
