Question

What is the speed of a rocket that travels 8000 meters in 12 seconds?

Answer 1

Find how much it travels in a second:
8000/12 = 666.666 m/s (or 2000/3 as a simple fraction)
Multiply by 3.6
666.666 * 3.6 = 2400 km/h

Answer 2

If you notice you could do it directly as well.
\[\frac{ 8000 }{ 12 }\times3.6=2400_{km/h}\]

Answer 3

it doesn't specify any units

speed can be mph, kph, m/s, yards per fortnight.

a perfectly good answer would be
8000m per 12 sec

Answer 4

If you wish to stick to sensible 'standard' units then kph is not the preferred SI unit

You should calculate the speed in m/s

8000/12 = 666.666 m/s