Answer:
a is 622
Step-by-step explanation:
8 times. I hope this helps
Answer:
The standard deviation of the sampling distribution of the sample wait times is of 0.8 minutes.
Step-by-step explanation:
Central Limit Theorem
The Central Limit Theorem establishes that, for a normally distributed random variable X, with mean
and standard deviation
, the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean
and standard deviation
.
For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30. Otherwise, the mean and the standard deviations holds, but the distribution will not be approximately normal.
Standard deviation 4 minutes.
This means that 
A sample of 25 wait times is randomly selected.
This means that 
What is the standard deviation of the sampling distribution of the sample wait times?

The standard deviation of the sampling distribution of the sample wait times is of 0.8 minutes.
Answer:
There should be a periodic maintanance for every 1.27months
Step-by-step explanation:
The step by step calculation explaining how frequent the equipment should receive periodic maintenance <em><u>(Which are the activities carried out on equipment based on a stipulated time interval for the purpose of maintaining a smooth operation of a machine or equipment or on other asset.)</u></em> can be seen in the attached image below.