Solution:
Demand function [tex]\mathrm{P}=\mathrm{D}(\mathrm{x})=210 / \mathrm{sqrt}(\mathrm{x})[/tex]
Marginal revenue = the number of items sold, x, times the price, p
Now, we are given the demand function as [tex]\mathrm{p}=210 / \mathrm{sqrt}(\mathrm{x})[/tex]
where x is the demand for units at a given price, p
=> Marginal revenue = [tex]\mathrm{R}(\mathrm{x})=\mathrm{x} * 210 / \mathrm{sqrt}(\mathrm{x})=[/tex] 210 multilply with sqrt(x) , --------------->(1)
Now, we need to find the marginal revenue hen x = 45 units , so we'll plug x = 45 in equation (1)
=> R(x) = 210 multiply with sqrt(45) = 1408.7228
Hence the marginal revenue is = $ 1409
