physics
posted by andrea on .
In 1954, Roger Bannister became the first human to run a mile in less than 4 minutes. Suppose that a runner on a straight track covers a distance of 1.00 mi in exactly 4.00 min.
1. What is his average speed in mi/h?
2. What is his average speed in ft/s?
3. What is his average speed in m/s?

1.00 mi in 4.00 min
1 mile/min = 60 mph
1 mile/4 min = 0.25 mi/min
1. 0.25 x 60 mi/hr = ? mph
2. 0.25 x 88 ft/sec = ? ft/sec
3. 0.25 x 26.8224 meters/sec = ? meters/sec 
should have added above,
1 mi = 5280 feet
1 mi = 1609.344 meters
1 mi/min = 60 mi/hr
1 mi/min = 88 ft/sec
1 mi/min = 26.8224 meters/sec
sorry for the confusion. I wish there was a 'do over' button. :) 
On March 27, 2004, the United States successfully tested the hypersonic X43A scramjet, which flew at Mach 7 (seven times the speed of sound) for 11.0 seconds.