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A record club has found that the marginal prot, P'(x), in cents, is given by P'(x) = - 0.0005x3 + 0.24x2 + 43.2x for xs 500, where x is the number of members currently enrolled in the club. 24 coo-'13,\") = 0'0005x3 + 024x2 +43.2x 6 A - l l l ' Approximate the total prot when 300 members are enrolled by oomputing the sum 2 P' (xi) Ax with Ax = 50. E 1910044 l 1 1 i=1 i 14,400 i j l E 3 9.600- ' .2 l 9 4 300- m . 2 l l 0 100 200 300 400 500 Number of members The total prot when 300 members are enrolled is approximately 3 (Round to the nearest cent as needed.)