The given equation is

Here we have to solve for n. First we need to get rid of the denominators and for that we do cross multiplication .

Now we need to isolate n. And for that we need to get rid of 12, by dividing both sides by 12



And that's the required value of n .
81, if you mean 9 Squared.
Answers:
1)
Mean = $349.2
Median = $352.5
Range = $210
2)
$499.90
3)
$355
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