Answer:
$6,000
Step-by-step explanation:
The mean value of a sample is assumed to be the same as the mean of the population. The mean of a uniformly distributed variable between 0 and 160 is:
[tex]M = \frac{0+160}{2}\\ M=\$80[/tex]
If the mean cost for each machine is $80, the mean aggregate cost for a sample of 75 machines is:
[tex]M_{75}=75*\$80\\M_{75}=\$6,000[/tex]
The mean aggregate maintenance cost is $6,000.