Marginal Revenue (MR)
This is the increase in Total Revenue resulting from the sale of an extra unit of output. Thus, if TRn-1 is Total Revenue from the sale of (n-1) units and TRn is total revenue from the sale of n units, then the marginal revenue of the nth unit is given as:
dTR = P(1 - 1/Ed) or TRn - TRn - 1
dQ