Question

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 black, the player loses 2 dollars. Find the expected value of the game. Express your answer in fraction form.

Answer 1

There are total of 52 cards

out of these,26 cards are red and 26 cards are black

P(win)=P(red) =26/52 =1/2

P(lose) =P(black) =26/52 =1/2

Expected value =(1/2)*(+1) +(1/2)*(-2)

                        = 1/2 -1

                        = -1/2