A car travels 170 miles in 9 hours. What is its average speed?
The average speed is 18.888889 mph.
How to work it out
- 1
Write down what you know: distance d = 170 miles, time t = 9 hours. You are asked for the speed v.
- 2
Use the formula speed = distance ÷ time:
- 3
Answer with the unit: 18.888889 mph.
- 4
The same formula rearranged: distance = speed × time (18.888889 × 9 = 170 miles) and time = distance ÷ speed (170 ÷ 18.888889 = 9 hours).
LaTeX source of the formulas on this page
\[ v = \frac{d}{t} = \frac{170}{9} = 18.888889\ \text{mph} \]
\[ v = \frac{d}{t} = \frac{170}{9} = \frac{170}{9} = 18.888889 \]How far at 18.888889 mph
| Time | Distance |
|---|---|
| 0.5 hours | 9.4444444 miles |
| 1 hour | 18.888889 miles |
| 2 hours | 37.777778 miles |
| 3 hours | 56.666667 miles |
| 4 hours | 75.555556 miles |
| 5 hours | 94.444444 miles |
Questions
What is the speed if a car travels 170 miles in 9 hours?
The average speed is 18.888889 mph.
How far does it go in 3 hours at that speed?
56.666667 miles.