Applied to a bill of Rs. 600, the difference between a single discount of 25% and two successive discounts of 10% and 15% is:

Correct option is D

Given:
Cost of the bill = Rs. 600
Single discount = 25%
Successive discounts = 10% and 15%
Formula Used:
Single Discount = Cost Price × $$\left( 1 - \frac{\text{Discount Percentage}}{100} \right)$$​​

Successive Discounts = Cost Price × $$\left( 1 - \frac{d_1}{100} \right) \times \left( 1 - \frac{d_2}{100} \right)$$​ where d₁ and d₂ are the first and second discounts.
Solution:
Single Discount Price $$= 600 \times \left( 1 - \frac{25}{100} \right) = 600 \times 0.75 = 450 \\$$​
Successive Discounts:
Price after First Discount $$= 600 \times \left( 1 - \frac{10}{100} \right) = 600 \times 0.90 = 540 \\$$​​

Price after Second Discount $$= 540 \times \left( 1 - \frac{15}{100} \right) = 540 \times 0.85 = 459 \\$$​​
Difference between the two prices = 459 - 450 = 9