1 mile = 5280 feet, hence 60 miles is 60x5280 = 316800 feet and this is traveled in 1 hour or 60 minutes. Hence per minute is 316800/60 = 5280 feet per minute. There is a short cut. If you multiply miles/hour by 88, you will get feet per minute. Similarly, to get feet per second from miles per hour, multiply mph by the fraction (22/15)