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About what percent of$x$ values lie between the mean and three standard deviations?

About what percent of$x$ values lie between the mean and one standard deviation?

About what percent of $x$values lie between the first and second standard deviations from the mean (both sides)?

A company manufactures rubber balls. The mean diameter of a ball is $12cm$with a standard deviation of 0.2 cm. Define the random variable $X$in words. $X=$______________.

About what percent of $x$ values lie between the first and third standard deviations(both sides)?

Use the following information to answer the next two exercises: The life of Sunshine CD players is normally distributed with mean of 4.1 years and a standard deviation of 1.3 years. A CD player is guaranteed for three years. We are interested in the length of time a CD player lasts.

$X~\_\_\_\_\_(\_\_\_\_\_,\_\_\_\_\_)$

How would you represent the area to the left of one in a probability statement?

What is the area to the right of one?

If the area to the left of $x$in a normal distribution is $0.123$, what is the area to the right of $x$?

If the area to the right of $x$ in a normal distribution is $0.543$, what is the area to the left of$x$?