If a bookstore owner buys 15 books less for Tk. 900 when the price of each book goes up by Tk. 3, than find the original price of a book.
A
Tk 20
B
Tk 18
C
Tk. 15
D
Tk. 12
Correct Answer: Tk. 12
900⁄x- 900⁄(x+3)= 15 Or, (x+15) (x-12)= 0 So, x=12