Question

the speed of sound is approximately 720 miles per hour at sea level. At this rate, how many feet does sound travel in 20 seconds?

Answer 1

Explanation:

`((720 miles)/(1 hour) )((1 hour)/(3600 seconds) ) ((5280 feet)/(1 mile) )`

Units cancel to get answer in feet per seconds.

720 x 1/3600 x 5280 = 1056 feet per seconds

1056 x 20 seconds = 21120 feet