A watch was sold at a loss of 10%. If it was sold for Rs.180 more, there would have been a gain of 5%. What is the cost price?  Choose one:	A) rs . 1200	B) rs . 1100	C) rs . 1300	D) rs . 1400	E) rs . 1000

Rationale: "90 % 105 % - - - - - - - - 15 % - - - - 180 100 % - - - - ? = > rs . 1200 answer : a"
Answer: A