Expected value Quiz
10 questions · easy to harder · Probability · score and step-by-step answers
How it works
- 10 questions, about 30 minutes (a timer counts down; you can hide it). Solve it right here: no sign-up.
- 2 questions have choices. For the others you type the answer: a number like 4, −2, 7/2 or 3.5, or for example x = 4, x = 2 or x = −3, (3, 5), 2x + 1. Use ^ for powers (x^2) and sqrt for √. Any form with the same value counts (7/2 = 3.5).
- One question at a time: Back, Next, Mark for review and the question list at the bottom. A calculator is on the screen.
- At the end: your percent and grade, every question right or wrong, why a wrong choice is wrong, and its step-by-step solution. Then practise the lesson with new questions.
Your answers and results are kept in this browser only, so you can close the page and come back.
1 Question 1
A game: win $10 with probability 15, lose $2 otherwise, expected value- A) E = $0.40
- B) E = $0.04
- C) E = $4
2 Question 2
A game: win $9 with probability 13, lose $3 otherwise, expected valueType the answer.
3 Question 3
Roll a die: win $12 on a 6, lose $2 otherwise, expected value- A) E ≈ $5
- B) E ≈ $0.33
- C) E ≈ $0.033
- D) E ≈ $3.3
4 Question 4
A game: win $4 with probability 12, lose $4 otherwise, is it fairType the answer.
5 Question 5
Roll a die: win $4 on an even number, lose $4 otherwise, is it fairType the answer.
6 Question 6
A game: win $20 with probability 110, lose $3 otherwise, expected valueType the answer.
7 Question 7
Pay $1 to play, roll a die, win $5 on a 6, is it fairType the answer.
8 Question 8
A raffle sells 100 tickets at $5, one prize of $200, expected valueType the answer.
9 Question 9
A raffle sells 50 tickets at $4, one prize of $100, expected valueType the answer.
10 Question 10
A game: win $5 with probability 12, win $1 with probability 14, lose $10 otherwise, expected valueType the answer.