Fixed cost 500 marginal cost 8 item sells for 30

fixed cost 500 marginal cost 8 item sells for 30.

Set up Cost Function C(x) where x is the number of items sold:
C(x) = Marginal Cost * x + Fixed Cost
C(x) = 8x + 500

Set up Revenue Function R(x) where x is the number of items sold:
R(x) = Revenue per item * items sold
R(x) = 30x

Set up break even function (Cost Equals Revenue)
C(x) = R(x)
8x + 500 = 30x

Subtract 8x from each side:
22x = 500

Divide each side by 22:
x = 22.727272 ~ 23 units for breakeven