Question

i travel distance of 10km and come back in 2 1/2 hours . what is my speed?

Answer 1

Distance = 10 km

Time taken = 2.5 hr

$speed = \frac{distance \: travelled}{time \: taken} \\ \\ = \frac{10}{2.5} km \: per \: hr \\ \\ = 4km \: per \: hr$
Hope it helps.

Answer 2

Distance=10km

Time=2½ hours

So speed = Distance/Time

= 10km/ 5/2 hours

=4km/h