A Firm Produces Two Products, "F" and "G", and the Production

A firm produces two products, "f" and "g", and the production process is such that one unit of f is always obtained with one unit of "g". If the demand curves for "f" and "g" are estimated to be: Q_f = 300 - P_f so that MR_f = 300 - 2Q_f) and Q_g = 400 - 2P_g so that MR_g = 200 - Q_g) and the marginal cost of production is MC = 50 + 3Q_j, where Q_j consists of one unit of each product, the firm will maximize profits if it sells 100 units of "f" and 100 units of "j".