By selling a book for 258, a bookseller gains 20%. For how much should he sell it to gain 30%?

Explanation

To solve the problem step by step, we will first find the cost price (CP) of the book using the given selling price (SP) and profit percentage, and then we will calculate the new selling price for a 30% profit.

### Step 1: Understand the relationship between Selling Price, Cost Price, and Profit Percentage

The relationship can be expressed as:
\[ \text{Selling Price (SP)} = \text{Cost Price (CP)} + \text{Profit} \]
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