Some articles were bought at 6 articles for Rs. 5 and sold at 5 articles for Rs. 6. Gain percent is:

Per-unit prices

• Buying: 6 for Rs. 5 ⇒ Cost price (CP) per article = Rs. 5 ÷ 6
• Selling: 5 for Rs. 6 ⇒ Selling price (SP) per article = Rs. 6 ÷ 5

Step 1: Gain per article
Gain = SP − CP = (6/5) − (5/6) = (36 − 25) ÷ 30 = 11/30

Step 2: Gain percent
Gain% = [(Gain) ÷ CP] × 100 = (11/30) ÷ (5/6) × 100= (11/30) × (6/5) × 100 = (66/150) × 100 = 44%

Final Answer: Gain percent = 44%.