A retailer bought a machine at a wholesale price of $81 and later on sold it after a 10% discount of the retail price. If the retailer made a profit equivalent to 20% of the whole price, what is the retail price of the machine?
Choices:
A) 81 B) 108 C) 120 D) 135 E) 160

Rationale: "my solution : wholesale price = 81 retail price , be = x he provides 10 % discount on retail price = x - 10 x / 100 this retail price = 20 % profit on wholesale price x - 10 x / 100 = 81 + 1 / 5 ( 81 ) x = 108 ; answer : b"
Answer: B