Ashopkeeper offers the following 3 schemes. Which scheme has the lowest discount percentage (all articles have same marked price)?
I. Two successive discounts of 10% and 10%
II. Buy 7 get 8
III. Buy 9 get 1 free

Let marked price = Rs. 100

Scheme I : After 1st discount of 10%, effective price = $$100-(\frac{10}{100}\times100)=Rs.$$ $$90$$

Similarly, after 2nd discount, effective price = Rs. 81

=> Discount offered = $$\frac{(100-81)}{100}\times100=19\%$$

Scheme II : Marked price of 8 = Rs. 800 and selling price of 7 = Rs. 700

=> Discount % = $$\frac{(800-700)}{800}\times100=12.5\%$$

Scheme III : Marked price of 10 = Rs. 1000 and selling price of 9 = Rs. 900

=> Discount % = $$\frac{(1000-900)}{1000}\times100=10\%$$

$$\therefore$$ Scheme III has the lowest discount percentage.

=> Ans - (B)