A car travels 20 miles in 9 hours. What is its average speed?
The average speed is 2.2222222 mph.
How to work it out
- 1
Write down what you know: distance d = 20 miles, time t = 9 hours. You are asked for the speed v.
- 2
Use the formula speed = distance ÷ time:
- 3
Answer with the unit: 2.2222222 mph.
- 4
The same formula rearranged: distance = speed × time (2.2222222 × 9 = 20 miles) and time = distance ÷ speed (20 ÷ 2.2222222 = 9 hours).
LaTeX source of the formulas on this page
\[ v = \frac{d}{t} = \frac{20}{9} = 2.2222222\ \text{mph} \]
\[ v = \frac{d}{t} = \frac{20}{9} = \frac{20}{9} = 2.2222222 \]How far at 2.2222222 mph
| Time | Distance |
|---|---|
| 0.5 hours | 1.1111111 miles |
| 1 hour | 2.2222222 miles |
| 2 hours | 4.4444444 miles |
| 3 hours | 6.6666667 miles |
| 4 hours | 8.8888889 miles |
| 5 hours | 11.111111 miles |
Questions
What is the speed if a car travels 20 miles in 9 hours?
The average speed is 2.2222222 mph.
How far does it go in 3 hours at that speed?
6.6666667 miles.