A car travels 490 km in 4 hours. What is its average speed?
The average speed is 122.5 km/h.
How to work it out
- 1
Write down what you know: distance d = 490 km, time t = 4 hours. You are asked for the speed v.
- 2
Use the formula speed = distance ÷ time:
- 3
Answer with the unit: 122.5 km/h.
- 4
The same formula rearranged: distance = speed × time (122.5 × 4 = 490 km) and time = distance ÷ speed (490 ÷ 122.5 = 4 hours).
LaTeX source of the formulas on this page
\[ v = \frac{d}{t} = \frac{490}{4} = 122.5\ \text{km/h} \]
\[ v = \frac{d}{t} = \frac{490}{4} = \frac{245}{2} = 122.5 \]How far at 122.5 km/h
| Time | Distance |
|---|---|
| 0.5 hours | 61.25 km |
| 1 hour | 122.5 km |
| 2 hours | 245 km |
| 3 hours | 367.5 km |
| 4 hours | 490 km |
| 5 hours | 612.5 km |
Questions
What is the speed if a car travels 490 km in 4 hours?
The average speed is 122.5 km/h.
How far does it go in 3 hours at that speed?
367.5 km.