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Increasing the standard deviation of a normal distribution makes the curve:
AShift to the left
BFatter and lower
CThinner and taller
DShift to the right
Answer & Solution
Correct answer: B. Fatter and lower
1. The area under the curve must equal one no matter what the deviation is.
2. A change in the standard deviation causes a change in the shape of the curve.
3. The curve becomes fatter or skinnier depending on that deviation.
4. A larger spread must therefore lower the peak to keep the total area at one.
_Source: OpenStax Introductory Statistics 2e (CC BY 4.0), Ch 6 'The Normal Distribution', sections 6.1-6.3_
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