Answer:
The original price of the novel is $ 21.
Step-by-step explanation:
Let x be the original price of the novel,
Discount percentage = 15%,
The amount of discount = 15% of the original price of the novel
= 15% of x

= 0.15x
Thus, the price of the book after discount = x - 0.15x
= 0.85x
According to the question,
0.85x = 17.85

Hence, the original price of the novel is $ 21.