50 miles per hour is the same as 73.33 ft per second. So if Morris is traveling 3 ft per second slower than Aneesha, he is traveling 70.33 ft per second. Converting that back to miles per hour, he is traveling at a rate of 47.95 mph
It would be nice to know some options, but here's Morris's speed. Since Morris is traveling at three feet per second, we want to change it to per hour. 3 * 3600 = 10800 feet per hour And we would want to convert that to miles per hour. 10800/5280 is about 2, more specifically 2.05 ish. So Morris is traveling 2 mph less then 50, or about 48 mph.