A ping pong ball is drawn at random from an urn consisting of balls numbered 20 through 28. A player wins 3 dollars if the number on the ball is odd and loses 3 dollars if the number is even. What is the expected value of his winnings? Round to 3 decimal places.
A card is drawn at random from a standard deck of playing cards (no jokers). If it is red, the player wins 1 dollar; if it is not red, the player loses 5 dollars. Find the expected value of the game.
In a class there are 18 students: 2 are 5' 6", 5 are 5'8", 5 are 5'10", 3 are 6', and 3 are 6' 2". A student is chosen at random. What is the student's expected height in inches? Round to the nearest tenth of an inch.
inches