Passengers using New York's MetroCard system must swipe the card at a rate between 10 and 40 inches per second, or else the card must be re-swiped through the card reader. Research shows that actual swipe rates by subway riders are uniformly distributed between 5 and 50 inches per second.
Determine the following to 2 decimal places:
a) Mean swipe rate - I got 27.50
b) Standard deviation of the swipe rate - I got 12.99
c) 1st Quartile - I got 16.25
d) 3rd Quartile - I got 38.75
e) What percentage of subway riders must re-swipe the card because they were outside the acceptable range?