Chapter 6.1 ex 2.
2.A card is drawn at random from a deck of playing cards. If it is red, the player wins 1 dollar; if it is black, the player loses 2 dollars. Find the expected value of the game.
\[ X = 1/2 - 2(1/2) = -1/2\]
(1/2) - 2*(1/2)
## [1] -0.5
4. In Las Vegas the roulette wheel has a 0 and a 00 and then the numbers 1 to 36 marked on equal slots; the wheel is spun and a ball stops randomly in one slot. When a player bets 1 dollar on a number, he receives 36 dollars if the ball stops on this number, for a net gain of 35 dollars; otherwise, he loses his dollar bet. Find the expected value for his winnings.
\[ X = 35(1/38) - (37/38)\]
35*(1/38) - (37/38)
## [1] -0.05263158