Normal probabilities with the z-table Quiz
10 questions · easy to harder · University Statistics · 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.
- 5 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
Normal: P(X < 60), mean 50, sd 10- A) P(X < 60) = 0.08413
- B) P(X < 60) = 8.413
- C) P(X < 60) = 0.8413
- D) P(X < 60) = 1
2 Question 2
Normal: P(X < 45), mean 50, sd 5Type the answer.
3 Question 3
Normal: P(X < 112), mean 100, sd 8- A) P(X < 112) = 0.9332
- B) P(X < 112) = 93.32
- C) P(X < 112) = 9.332
- D) P(X < 112) = 1.5
4 Question 4
Normal: P(X > 40), mean 50, sd 10Type the answer.
5 Question 5
Normal: P(40 < X < 65), mean 50, sd 10- A) 0.7745
- B) 7.745
- C) 1.5
- D) 0.07745
6 Question 6
Normal: P(X > 83), mean 75, sd 6Type the answer.
7 Question 7
Normal: P(X < 34), mean 40, sd 5- A) P(X < 34) = 0.1151
- B) P(X < 34) = 0.01151
- C) P(X < 34) = 1.151
8 Question 8
Normal: P(X < 63.5), mean 60, sd 2.5Type the answer.
9 Question 9
Normal: P(X > 71.2), mean 65, sd 4- A) 1.55
- B) 0.0606
- C) 0.9394
- D) 0.606
10 Question 10
Normal: P(X < 480), mean 500, sd 25Type the answer.