By Selling 4 articles for 1 rupee, a man losses 50%. Had he sold 2 articles per rupee, then what will be the profit percentage?

For first case, SP = 1/4 per article

CP = SP + loss = 1/4 + 50%(CP) = 1/4 + CP/2

⇒ CP/2 = ¼

⇒ CP = Rs 1/2

Now, for second part,

⇒ SP = Rs. 1/2 per article.

⇒ Profit = SP - CP = 1/2 - 1/2 = 0