1.  A manufacturer sells a pair of glasses to a wholesale dealer at a profit of 18%. The wholesaler sells the same to retailer at a profit of 20%. The retailer in turn sells them to a customer for ₹ 30.09, there by earning a profit of 25%. The cost price for the manufacturer is:
A. ₹ 15
B. ₹ 16
C. ₹ 17
D. ₹ 18

Answer: Option C

Explanation:

Let the cost price for the manufacturer be ₹ X.

Then, 125% of 120% of 118% of X = 30.09.

⇒ (125/100 x 120/100 x 118/100 x X) = 3009/100

∴ 177/100 X = 3009/100 => X = ₹ 17