Example 1
A cyclist travels at 12 km/h for 2 hours. How far do they travel?
- Use distance = speed × time.
- Speed is 12 km/h and time is 2 hours
- 12 × 2 = 24
So: The cyclist travels 24 km.
Back to National 4
Topic
Speed, Distance and Time
Speed, distance and time questions connect how far something travels, how long it travels for, and its average speed.
Topic explanation
Speed tells you how much distance is covered in one unit of time, such as kilometres per hour.
Before calculating, make sure the units match. If speed is in km/h, time should be in hours.
Average speed describes the whole journey. It can include slower and faster parts, but it uses total distance and total time.
Quick methods
- Distance
- Distance = speed × time
- Speed
- Speed = distance divided by time
- Time
- Time = distance divided by speed
- Minutes
- Change minutes to hours before using km/h
Worked examples
Example 2
A car travels 150 km in 3 hours. What is its average speed?
- Use speed = distance divided by time.
- Distance is 150 km and time is 3 hours.
- 150 divided by 3 = 50
So: The average speed is 50 km/h.
Example 3
A runner travels 7.5 km at 10 km/h. How long does the run take?
- Use time = distance divided by speed.
- 7.5 divided by 10 = 0.75 hours
- 0.75 hours is 45 minutes because 0.75 × 60 = 45
So: The run takes 45 minutes.