The selling price of a book, including the sales tax, is ₹ 956.34. The rate of sales tax is 10%. If the shopkeeper has made a profit of 15%, then the cost price of the book is:

Let the cost price of the book = C

Sales tax = 10%

Price of the book with sales tax = $$\frac{110}{100}C$$

Profit = 15%

Selling price of the book = ₹ 956.34

$$\Rightarrow$$  $$\frac{115}{100}\times\frac{110}{100}C$$ = 956.34

$$\Rightarrow$$  $$C=\frac{956340}{115\times11}$$

$$\Rightarrow$$  $$C=\frac{86940}{115}$$

$$\Rightarrow$$  $$C=\frac{3780}{5}$$

$$\Rightarrow$$  $$C=756$$

$$\therefore\ $$Cost price of the book = ₹ 756

Hence, the correct answer is Option D