A trader offers several discount schemes. Choose the scheme that provides the lowest selling price from the following options.

Correct option is C

Solution:

Option A - A single discount of 72%:
The selling price after a 72% discount is 28% of the original price. Mathematically, this is:
Selling Price =$$P \times (1 - 0.7$$​2) = 0.28P

Option B - Buy one, get one free:
This means the trader gives one additional product for every product purchased, so the effective price per item is halved.
Effective Price =$$\frac{P}{2}$$= 0.50P​​

Option C - Buy one, get three free:
For every one product bought, four products are received. Thus, the price per product is:
Effective Price = $$\frac{P}{4}$$= 0.25P​​

Option D - Buy two, get five free:
For every two products bought, seven are received. Hence, the price per product is:
Effective Price =$$\frac{2P}{7}$$$$\approx 0.2857P$$​​​

Conclusion:

The lowest price is given by Option C, where you get four products for the price of one, making the price per product 0.25P.