A car travels 90 miles in 10 hours. What is its average speed?
The average speed is 9 mph.
How to work it out
- 1
Write down what you know: distance d = 90 miles, time t = 10 hours. You are asked for the speed v.
- 2
Use the formula speed = distance ÷ time:
- 3
Answer with the unit: 9 mph.
- 4
The same formula rearranged: distance = speed × time (9 × 10 = 90 miles) and time = distance ÷ speed (90 ÷ 9 = 10 hours).
LaTeX source of the formulas on this page
\[ v = \frac{d}{t} = \frac{90}{10} = 9\ \text{mph} \]
\[ v = \frac{d}{t} = \frac{90}{10} = 9 \]How far at 9 mph
| Time | Distance |
|---|---|
| 0.5 hours | 4.5 miles |
| 1 hour | 9 miles |
| 2 hours | 18 miles |
| 3 hours | 27 miles |
| 4 hours | 36 miles |
| 5 hours | 45 miles |
Questions
What is the speed if a car travels 90 miles in 10 hours?
The average speed is 9 mph.
How far does it go in 3 hours at that speed?
27 miles.