We know that the elevator can rise 480 feet in 30 seconds. From this, we can figure out how many feet the elevator rises per second.
480 feet / 30 seconds = 16 feet / 1 second
This means that the elevator rises 16 feet in 1 second. However, the question asks how many feet the elevator can rise per minute, so we have to multiply this amount by 60, because there are 60 seconds in a minute.
16 feet * 60 = 960 feet per minute.
Therefore, the high speed elevator can rise 960 feet in a minute.
So I worked this out by adding all the houses together. I whole hour is two half hours. So it made it 2/3 of an hour. so I added everything together = 1/3+ 1/3+ 1/3 +1/3+ 1.5/3 = 3 1/2 Hours to walk.