Question

A person preparing for Olympics Games ran 9 km in 1 hour and 20 minutes, and then 12 km in 1 hour and 40 minutes. What is the average speed in km/hr?​

Answer 1

There are 60 minutes in one hour. To make the 20 minutes into an hour, we have to multiply it by 3, creating 60 minutes. In this case, we would also have to multiple the km by 3, making 27 km. Whatever you do to the denominator (multiply or divide), you have to do the same to the numerator. 9/20 times 3 equals 27/60 (top is distance, and bottom is time). Distance over time equals velocity.