Seller selling an apple for Rs.17, a Seller loses 1/6th of what it costs him. The CP of the apple is?
Pick.
A) 10
B) 12
C) 18
D) 19
E) 20

Rationale: "sp = 17 loss = cp 18 loss = cp − sp = cp − 17 ⇒ cp 18 = cp − 17 ⇒ 17 cp 18 = 17 ⇒ cp 18 = 1 ⇒ cp = 18 c"
Answer: C