Restaurants A, B, C, and D give the following offers:
A: one mocktail free for every two purchased
B: one mocktail free for every three purchased
C: two mocktails free for every six purchased
D: 30% discount on each mocktail
If all restaurants have the same marked price for each mocktail, in which restaurant would you pay the least if you drank eight mocktails?

Correct option is D

Solution:
Assume the marked price of one mocktail = 1 unit.
Restaurant A
Offer: Buy 2, get 1 free (pay for 2, get 3)
To drink 8 mocktails, you pay for 6 and get 3 free (total 9, but drink only 8).
Cost = 6 units
Restaurant B
Offer: Buy 3, get 1 free (pay for 3, get 4)
To drink 8 mocktails, pay for 6 and get 2 free.
Cost = 6 units
Restaurant C
Offer: Buy 6, get 2 free
Pay for 6 and get exactly 8 mocktails.
Cost = 6 units
Restaurant D
Offer: 30% discount on each mocktail
Cost per mocktail = 70%
Total cost = 8 × 0.7 = 5.6 units

Comparison:
• A = 6
• B = 6
• C = 6
• D = 5.6
Correct answer:
(d) D