The price of a Maruti car rises by $30$% while the sales of the car came down by $20$%. What is the percent change in the total revenue?
Let the initial price be 'P' and initial sales be 'S'
So, the initial revenue C = P*S
Pnew = 1.3P and Snew = 0.8S
$\therefore$ Cnew = Pnew*Snew = 1.3P*0.8S = 1.04C
So, there is a 4% increase in total revenue.
C is the answer.