A bookseller sells a book at a gain of 10%. if he had bought it at 4% less and sold it for ₹ 6 more, he would have gained 118 3/ 4%. The CP of the book is?

Let CP = N
Then, SP = 110N / 100 = ₹ 11N/10
Now, CP = 96% of N = 96N/100 = ₹ 24N/25
Now, according to the question,
SP = ₹ (11N/10) + 6
∴ (11N/10) + 6 = 118³/₄% of 24N/25
⇒ (11N + 60)/10 = (475/400) x (24N/25) = 57N/50
⇒ 550N + 3000 = 570N
⇒ 20N = 3000
∴ N = 3000/20 = 150
∴ CP = ₹ 150