If a discount of 10% is allowed on the marked price of an article, a shopkeeper gets a profit of 25%. If he offers a discount of 25% on the marked price of the same article, then his percentage profit/loss will be:

Let the Market price of the article Rs 100

Discount = 10% 

% Selling price = 90 % of Rs 100

$$\Rightarrow \dfrac{90}{100} \times 100 $$

$$\Rightarrow 90 $$ 

profit = 25%

so cost price = $$ 90 \times \dfrac{100} {125} $$

$$\Rightarrow Rs 72 $$

Now, if the discount is 25% then

selling price = $$ \dfrac{75}{100} \times 100 $$

$$\Rightarrow 75 $$

Required profit % = $$\dfrac {75-72} {72 }\times 100$$

$$\Rightarrow \dfrac{3}{72} \times 100 $$

$$\Rightarrow \dfrac{25}{6} $$

$$\Rightarrow 4 \dfrac{1}{6} $$ % Ans