What is the effective discount per cent (rounded off to 2 decimal places) if a shopkeeper offers a scheme, “buy five and get one free”?

Correct option is D

​Given:
​One free article is offered on buying 5 article
​Formula Used:
​Discount percentage =$$\frac{Discount}{MP}$$​​×100
​Solution:
​let the price of one article be x
​As per the given question:
​MP = 6x
​Discount = 1x
​Discount percentage = $$\frac{1x}{6x}×100= 16.66.. ≈ 16.67 \%$$​​​
​Alternate Method:
​If one free article is offered on buying 5 article
​Then; MP should be 6 unit and discount = 1 unit
​Discount% = $$\frac{1}{6}×100=16.66.. ≈ 16.67\%$$​