Two normal curves, A and B, have the same standard deviation. A has mean 40 and B has mean 60. Which statement is true?

B is flatter and wider than ACorrect answerYour answerThey have the same shape, and B is A moved 20 to the rightCorrect answerYour answerB is taller and narrower than ACorrect answerYour answerB encloses more area than ACorrect answerYour answer

Show the answer and explanation

CorrectNot quiteAnswer B

Correct answer: B

The standard deviation sets the shape; equal standard deviations mean identical shapes.
The mean sets the position: B's centre is 20 units to the right of A's.

Worth noting

Every normal curve encloses area exactly 1.

Concept: Reading the mean and spread from curves
Typical timeTypical: 90 s
Your timeYours: —

The rule this testsThe normal curve

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Ten questions from Normal Distribution, at your own pace.

Two normal curves, A and B, have the same standard deviation. A has mean 40 and B has mean 60. Which statement is true?

Explanation