$X$ Is a Normally Distributed Random Variable with a Standard Deviation

question 60

Multiple Choice

$X$ is a normally distributed random variable with a standard deviation of $2.00$ . Find the mean of $X$ if $12.71 \%$ of the area under the distribution curve lies to the right of $10.28$ . (Note: the diagram is not necessarily to scale.)

• A) 8.7
• B) 7.5
• C) 8.0
• D) 9.6

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