Consider the following
q = 7LK + 4L2 − (1/3)L3.
Given the following expressions for the marginal productivity of each input:
MPL = 7K + 8L − L2 and MPK = 7L
Assuming capital is plotted on the vertical axis and labor is plotted on the horizointal axis, determine the value of the marginal rate of technical substitution when K = 20
and L = 10
(Round your answer up to two decimal places and include the proper sign.)
MRTS = ________________