1.05 Interpreting and comparing z-scores
Interactive practice questions
Complete the following statements for a normal distribution using the empirical rule.
What percentage of the scores lie within $1$1 standard deviation of the mean?
$34%$34%
$68%$68%
$32%$32%
$99.7%$99.7%
$95%$95%
What percentage of the scores lie within $2$2 standard deviations of the mean?
$99.7%$99.7%
$95%$95%
$5%$5%
$47.5%$47.5%
$68%$68%
What percentage of the scores lie within $3$3 standard deviations of the mean?
$95%$95%
$99.7%$99.7%
$49.85%$49.85%
$68%$68%
$0.03%$0.03%
In a normal distribution, what percentage of scores lie between the mean and $1$1 standard deviation above the mean? Use the empirical rule to find your answer.
In a normal distribution, what percentage of scores lie between the mean and $2$2 standard deviations below the mean? Use the empirical rule to find your answer.
Consider the normal distribution shown below. Each unit on the horizontal axis indicates $1$1 standard deviation.