Question

A high-speed elevator can rise 480 feet in 30 seconds. Which expression represents the rate , in feet per minute, of the elevator?

Answer 1

velocity=distance divided by time, v=d/t in this case:

v=480/30=16 ft/s

Answer 2

We can find the feet per second by dividing 480 by 30. This gets us that the elevator rises 16 feet per second. Since we are trying to find the rate in feet per minute, we will multiply 16 by 60, which will get us 960 ft/min. You could also note that 30 seconds is half of one minute, so you could multiply 480 by 2 to get the same 960 ft/min.

:)