The profit function, p(x) is the difference between the revenue and cost function of the shirt sales, Hence, the profit function is 8x - 20
Given the Parameters :
The profit function can be expressed thus ::
P(x) = R(x) - C(x)
P(x) = 15x - (7x + 20)
P(x) = 15x - 7x - 20
P(x) = 8x - 20
Therefore, the profit function is 8x - 20.
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