A car travels 170 km in 12 hours. What is its average speed?

The average speed is 14.166667 km/h.

v = \frac{d}{t} = \frac{170}{12} = 14.166667\ \text{km/h}

How to work it out

1
Write down what you know: distance d = 170 km, time t = 12 hours. You are asked for the speed v.
2
Use the formula speed = distance ÷ time:
$v = \frac{d}{t} = \frac{170}{12} = \frac{85}{6} = 14.166667$
3
Answer with the unit: 14.166667 km/h.
4
The same formula rearranged: distance = speed × time (14.166667 × 12 = 170 km) and time = distance ÷ speed (170 ÷ 14.166667 = 12 hours).

LaTeX source of the formulas on this page

\[ v = \frac{d}{t} = \frac{170}{12} = 14.166667\ \text{km/h} \]
\[ v = \frac{d}{t} = \frac{170}{12} = \frac{85}{6} = 14.166667 \]

What is the speed if a car travels 170 km in 12 hours?

The average speed is 14.166667 km/h.

How far does it go in 3 hours at that speed?

42.5 km.