A girl on the XC team must run the 5KM course in less than 20 min. What is the average speed of a 20 min runner, in Km per hour? In meters per second?

Question

Can you please have the answer be to two decimal places, and can you explain it so I can understand it? Thanks!

Answer 1

In order to run 5 Km in 20 minutes, how many Km does one have to run in 1 minute?

That would be 5 Km/20 minutes = 0.25 Km per minute, or a quarter of a kilometer in 1 minute.

This would be the average speed per minute.  To get it per hour, we know there are 60 minutes in hour, so...

0.25 Km/min x 60 min/hour = 15.00 Km/hour.

To get this into meters per second, we have to change Km to meters and minutes to seconds.  There are 1000 meters in 1 Km, and there are 60 seconds in 1 minute.

0.25 Km/minute x 1000 meters/Km x 1 minute/60 seconds = 4.17 meters per second.