What is speed? Definition. Units of speed. Calculate one of distance, speed or time given the other two variables.

Multiplication and division skills are useful when solving speed, distance and time problems. It may be useful to review how to calculate speed, distance and time.

For example, if you know the speed of any vehicle and the distance covered by that vehicle, then you can easily calculate the time taken for the entire journey by using the above formula.

They would like to use knowledge about how far away galaxies are to calculate their typical brightness. They can use distance to calculate speed, and speed to calculate distance, but not both at once.