7

Set 3: Probability (Advanced)

Explanation

Answer: B

PROBLEM

In a game, you win $71 with probability 20% and $19 with probability 30%. What is the expected value?

In a game, you win $71 with probability 20% and $19 with probability 30%. What is the expected value?

A.

14.900000000000002

B.

19.900000000000002

✓ Correct
C.

24.900000000000002

D.

39.800000000000004

Detailed Explanation

Choice B is the best answer. E = 71(0.2) + 19(0.3) = 14.200000000000001 + 5.7 = $19.900000000000002

Why others are wrong:
A: 14.900000000000002 is incorrect because it does not satisfy the equation.
C: 24.900000000000002 is incorrect because it does not satisfy the equation.
D: 39.800000000000004 is incorrect because it does not satisfy the equation.