Provide an appropriate response.
-Find the z-score corresponding to the given value and use the z-score to determine whether the value is unusual. Consider a score to be unusual if it is at least three standard deviations above or
Below the mean. Round to the z-score to two decimal places, if necessary.
A department store, on average, has daily sales of $29,016.01. The standard deviation of sales is $
1500. On Tuesday, the store sold $35,503.73 worth of goods.
A)4.54, not unusual
B)4.33, unusual
C)4.64, unusual
D)3.46, not unusual

Question

Provide an appropriate response.
-Find the z-score corresponding to the given value and use the z-score to determine whether the value is unusual. Consider a score to be unusual if it is at least three standard deviations above or
Below the mean. Round to the z-score to two decimal places, if necessary.
A department store, on average, has daily sales of $29,016.01. The standard deviation of sales is $
1500. On Tuesday, the store sold $35,503.73 worth of goods. 
A)4.54, not unusual
B)4.33, unusual
C)4.64, unusual
D)3.46, not unusual

Quizplus · Accepted Answer

To find the z-score, use the formula $z = \frac{(X - \mu)}{\sigma}$, where $X$ is the value in question, $\mu$ is the mean, and $\sigma$ is the standard deviation. Plugging in the given values: $z = \frac{(35503.73 - 29016.01)}{1500} = 4.33$. A z-score of 4.33 is more than three standard deviations away from the mean, making it unusual.

Provide an Appropriate Response