# Bob roller skates 48 km in 4 hours. What is his average speed in kilometers per hour?

##### 1 Answer
May 21, 2017

His average speed is $\text{12 km/hr}$.

#### Explanation:

Remember the triangle of Speed, Distance and Time. If you remember it, you'll ace these kinda questions.

I had trouble with these formulas but the triangle helped me a LOT! Anyways, let's get back to the question. The formula for average speed is pretty much the same as the formula for just speed. The average speed formula is

$\text{Average speed" = "Total Distance"/"Total Time}$

So......

$\text{48 km"/"4 hr" = "12 km/hr}$

My source

I hope this explanation helps you!