Question: A firm uses inputs K, L and R to manufacture good Q. It has a budget of £828 and its production function (for positive values of Q) is
Q = 20K + 16L + 12R - 0.2K2 - 0.1L2 - 0.3R2
If PK = £20, PL = £10 and PR = £6, what is the maximum output it can produce? Assume that second-order conditions for a maximum are satisfied for the relevant Lagrangian.