Marginal revenue

Marginal revenue (MR) is defined as the change in ($\Delta$) total revenue (TR) as a firm sells one more or one less unit of its output (Q ).

${\text{MR}}$ = ${\frac {\Delta {\text{TR}}}{\Delta {\text{Q}}}}$

Average revenue (AR)is the total revenue (TR) divided by output (Q )or the revenue earned on average for each unit sold.

${\text{AR}}$ = ${\frac {\text{TR}}{\text{Q}}}$