Answer:not enough information
Step-by-step explanation:
Answer:
12.54
Step-by-step explanation:
just multiply 12×0.045 and add the 12.
I hope and this helps.
Have a good day.
Good luck
Answer:
The standard deviation of number of hours worked per week for these workers is 3.91.
Step-by-step explanation:
Problems of normally distributed samples can be solved using the z-score formula.
In a set with mean
and standard deviation
, the zscore of a measure X is given by
![Z = \frac{X - \mu}{\sigma}](https://tex.z-dn.net/?f=Z%20%3D%20%5Cfrac%7BX%20-%20%5Cmu%7D%7B%5Csigma%7D)
After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X. Subtracting 1 by the pvalue, we This p-value is the probability that the value of the measure is greater than X.
In this problem we have that:
The average number of hours worked per week is 43.4, so
.
Suppose 12% of these workers work more than 48 hours. Based on this percentage, what is the standard deviation of number of hours worked per week for these workers.
This means that the Z score of
has a pvalue of 0.88. This is Z between 1.17 and 1.18. So we use
.
![Z = \frac{X - \mu}{\sigma}](https://tex.z-dn.net/?f=Z%20%3D%20%5Cfrac%7BX%20-%20%5Cmu%7D%7B%5Csigma%7D)
![1.175 = \frac{48 - 43.4}{\sigma}](https://tex.z-dn.net/?f=1.175%20%3D%20%5Cfrac%7B48%20-%2043.4%7D%7B%5Csigma%7D)
![1.175\sigma = 4.6](https://tex.z-dn.net/?f=1.175%5Csigma%20%3D%204.6)
![\sigma = \frac{4.6}{1.175}](https://tex.z-dn.net/?f=%5Csigma%20%3D%20%5Cfrac%7B4.6%7D%7B1.175%7D)
![\sigma = 3.91](https://tex.z-dn.net/?f=%5Csigma%20%3D%203.91)
The standard deviation of number of hours worked per week for these workers is 3.91.