The demand for a certain product is represented by the function $p = 150+10x - x^2$ (in Rs.) where $x$ is the number of units demanded and $p$ is the price per unit, then the value of marginal revenue, when 10 units are sold, is

Rs.50

The correct answer is Option (1) → Rs.50 **

Demand function: $p=150+10x - x^2$.

Total revenue: $R = px = x(150+10x - x^2)=150x+10x^2 - x^3$.

Marginal revenue $=\frac{dR}{dx}$.

$\frac{dR}{dx}=150+20x - 3x^2$.

At $x=10$:

$MR = 150 + 20(10) - 3(10)^2$

$MR = 150 + 200 - 300 = 50$

Marginal revenue = 50