Question

A person who runs the 100-yard dash in 10.1 seconds has an average speed of 9.9 yards/second. Convert 9.9 yards/second to miles/hour?

Answer 1

`(9.9xx60xx60)/1760 = 20.25` miles per hour

Explanation:

`9.9` yards per second means that `9.9` yards are run in `1` second.

Calculate the distance this would be in one minute `(xx60)` and then in one hour `(xx60)`

`9.9 xx60xx60 = 35,640` yards in `1` hour.

`1` mile = `1760` yards.

Find the number of miles in `35,640` yards `(div 1760)`

`35640/1760 = 20.25` miles

`9.9 " yards per sec" = 20.25 " miles per hour"`

In one calculation:

`(9.9xx60xx60)/1760 = 20.25`