Expected value

1. 1.
   A game costs $2 to play. You win $50 with probability 15, otherwise nothing. What is the expected profit per game, in dollars?
2. 2.
   A random variable X has P(X=1) = 413, P(X=2) = 313, P(X=3) = 213, P(X=4) = 413. Find E(X) to two decimal places.
3. 3.
   A game costs $2 to play. You win $5 with probability 110, otherwise nothing. What is the expected profit per game, in dollars?
4. 4.
   A random variable X has P(X=1) = 17, P(X=2) = 27, P(X=3) = 37, P(X=4) = 17. Find E(X) to two decimal places.
5. 5.
   A random variable X has P(X=1) = 412, P(X=2) = 112, P(X=3) = 312, P(X=4) = 412. Find E(X) to two decimal places.
6. 6.
   A random variable X has P(X=1) = 211, P(X=2) = 211, P(X=3) = 311, P(X=4) = 411. Find E(X) to two decimal places.
7. 7.
   A game costs $1 to play. You win $10 with probability 15, otherwise nothing. What is the expected profit per game, in dollars?
8. 8.
   A random variable X has P(X=1) = 27, P(X=2) = 17, P(X=3) = 27, P(X=4) = 27. Find E(X) to two decimal places.
9. 9.
   A game costs $3 to play. You win $10 with probability 14, otherwise nothing. What is the expected profit per game, in dollars?
10. 10.
    A random variable X has P(X=1) = 312, P(X=2) = 312, P(X=3) = 312, P(X=4) = 312. Find E(X) to two decimal places.
11. 11.
    A game costs $2 to play. You win $20 with probability 14, otherwise nothing. What is the expected profit per game, in dollars?
12. 12.
    A random variable X has P(X=1) = 411, P(X=2) = 211, P(X=3) = 111, P(X=4) = 411. Find E(X) to two decimal places.
13. 13.
    A game costs $2 to play. You win $10 with probability 14, otherwise nothing. What is the expected profit per game, in dollars?
14. 14.
    A game costs $3 to play. You win $50 with probability 14, otherwise nothing. What is the expected profit per game, in dollars?
15. 15.
    A random variable X has P(X=1) = 110, P(X=2) = 110, P(X=3) = 410, P(X=4) = 410. Find E(X) to two decimal places.
16. 16.
    A random variable X has P(X=1) = 310, P(X=2) = 110, P(X=3) = 410, P(X=4) = 210. Find E(X) to two decimal places.
17. 17.
    A game costs $1 to play. You win $5 with probability 110, otherwise nothing. What is the expected profit per game, in dollars?
18. 18.
    A game costs $4 to play. You win $10 with probability 15, otherwise nothing. What is the expected profit per game, in dollars?
19. 19.
    A random variable X has P(X=1) = 210, P(X=2) = 410, P(X=3) = 210, P(X=4) = 210. Find E(X) to two decimal places.
20. 20.
    A random variable X has P(X=1) = 18, P(X=2) = 28, P(X=3) = 38, P(X=4) = 28. Find E(X) to two decimal places.

Free maths worksheets and practice: rocketdigits.com/learn/expected-value