A manufacturer fixes his selling price $$33\frac{1}{3}$$% over the cost of production. If cost of production goes up by 12% and manufacturer raises his selling price by 10% , his percentage profit is = ?

Let the CP₁ of Product= 300
Initial SP₁ = 300 + $$33\frac{1}{3}$$% of 300 = 300 + 100 = 400
Now, If cost of the production goes up by 12%.
∴ CP₂ = 300 + 12% of 300 = 300 + 36 = 336
Now SP₂ = 400 + 10% of 400 = 400 + 40 = 440
Profit = 440 - 336 = 104
Profit % $$ = \frac{{104}}{{336}} \times 100 = 30\frac{{20}}{{21}}\% $$