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The time in hours that a technician requires to perform preventative maintenance on an air conditioning...

The time in hours that a technician requires to perform preventative maintenance on an air conditioning unit has a mean time of one (1) hour and a standard deviation also of one (1) hour. Your company has a contract to maintain 70 of these units in an apartment building. You must schedule technicians' time for a visti to this building.

Consider the 70 air conditioners as a simple random sample from all air conditioning units of this type.

a. What is the samplng distribution for the mean time spent working on these air conditioning units. Remember a distribution describes the shape center and spread. Explain fully.

b.What is the probability that the average maintenance time spent on these 70 units exceeds 1.1 hours?
Enter your final answer below, Round to 4 decimal places.

c. What is the probability that the average maintenance time spent on these 70 units exceeds 1.25 hours?

d. Is it safe to budget an average of 1.1 hours for each unit? Or should you budget an average of 1.25 hours for each unit? Why?

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Expert Solution

milcah answered 1 year ago
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