Total costs equal total ▼ fixed marginal costs plus total ▼ marginal variable costs. ▼ average fixed marginal variable total costs equal total costs divided by output ( ▼ atc vc fc afc mc avc tc = tc/q). average ▼ fixed variable marginal costs equal total variable costs divided by output ( ▼ fc avc mc atc afc tc vc = tvc/q). average ▼ variable fixed marginal costs equal total fixed costs divided by output ( ▼ tc fc atc afc avc mc vc = tfc/q). ▼ variable marginal fixed cost equals the change in ▼ variable fixed total cost divided by the change in output ( ▼ fc mc avc vc afc tc atc = upper delta ▼ afc avc mc vc tc fc atc /upper deltaq, where the greek letter upper delta, delta, means "change in"). the marginal cost curve intersects the ▼ minimum maximum point of the average total cost curve and the ▼ minimum maximum point of the average variable cost curve.