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A record club has found that the marginal profit, P'(x), in 24,000 P'(x) = - 0.0008x3 + 0:30x2 + 57.4x cents, is given by P'(x) = - 0.0008x + 0.30x + 57.4x for x $ 400, where x is the number of members currently 19,200- enrolled in the club. Approximate the total profit when 240 14,400- members are enrolled by computing the sum Marginal profit (in cents) 6 9,600- [ P' (x; ) 4x with Ax = 40. 4,800 i =1 100 200 300 400 Number of members . . . The total profit when 240 members are enrolled is approximately $ (Round to the nearest cent as needed.)