A cross country runner runs 100 km in 80 minutes. What is his average speed?

1 Answer

Divide the distance (#d#) by time taken.

Explanation:

Use the equation

#d=rt#

where distance (#d#) is equal to the product of rate (#r#) and time (#t#).

Now, the distance and time are given. So we have to rearrange the equation to solve for #r#:

#d=rt#

#((d))/t=((rt))/t#

#r=d/t#

Now, let's plug in the values we have been given to find the rate:

#r=d/t#

#r=(100" km")/(80 " min")#

#r=1.25 " km/min"#

I hope that helps!

P.S. One thing to note is, as the original contributor mentioned, this model is not realistic, as it is impossible for a human to run this fast in real life.