The cost price of 20 articles is the same as the selling price of x articles. If the profit is 25%, then the value of x is:

Given Data

• Cost price of 20 articles = Selling price of x articles
• Profit = 25%
• Required: value of x

Step 1: Model CP and SP per articleLet CP per article = Rs. cWith 25% profit, SP per article = c × 1.25

Step 2: Set up the equality20c = x × (1.25c)Cancel c (c > 0): 20 = 1.25x ⇒ x = 20 ÷ 1.25 = 16

Checks & Common Pitfalls

• Profit increases SP, so fewer articles are needed on the SP side for equality.
• Do not forget to cancel the common factor c to simplify.

Final Answerx = 16.