# Lesson 3: Calculating Speed

### Let’s calculate average speed

Often calculating the average speed is simple using the formula

**speed = distance / time**

But sometimes you are given two different speeds used for some periods of time, or over some distances. In these instances, other formulas exist for calculating the average speed. These types of problems might be useful to you in real life, and often appear on standardized tests, so it is helpful to learn these formulas and methods.