A car travels 390 miles in 11 hours. What is its average speed?
The average speed is 35.454545 mph.
How to work it out
- 1
Write down what you know: distance d = 390 miles, time t = 11 hours. You are asked for the speed v.
- 2
Use the formula speed = distance ÷ time:
- 3
Answer with the unit: 35.454545 mph.
- 4
The same formula rearranged: distance = speed × time (35.454545 × 11 = 390 miles) and time = distance ÷ speed (390 ÷ 35.454545 = 11 hours).
LaTeX source of the formulas on this page
\[ v = \frac{d}{t} = \frac{390}{11} = 35.454545\ \text{mph} \]
\[ v = \frac{d}{t} = \frac{390}{11} = \frac{390}{11} = 35.454545 \]How far at 35.454545 mph
| Time | Distance |
|---|---|
| 0.5 hours | 17.727273 miles |
| 1 hour | 35.454545 miles |
| 2 hours | 70.909091 miles |
| 3 hours | 106.36364 miles |
| 4 hours | 141.81818 miles |
| 5 hours | 177.27273 miles |
Questions
What is the speed if a car travels 390 miles in 11 hours?
The average speed is 35.454545 mph.
How far does it go in 3 hours at that speed?
106.36364 miles.