Ramesh sells rice at ₹36 per kg, which he purchased for ₹30 per kg. Moreover, he gives only 800 g of rice instead of 1 kg while selling. Find the actual profit percentage of Ramesh.

Correct — A. Cost the goods he actually hands over, not the kilogram he charges for.

What the customer pays: ₹36
What Ramesh parts with: 800 g, which cost him 0.8 × 30 = ₹24

Profit = 36 − 24 = ₹12
Profit % = 12/24 × 100 = 50% → option (a)

Compounding the two gains gives the same figure: 1.20 on price × 1.25 on weight = 1.50.

Why the others are wrong

• (b)
  46% would need the 800 g to have cost about ₹24.66. It cost exactly ₹24, being 0.8 × ₹30, so the profit is ₹12 on ₹24 and no rounding turns that into 46.
• (c)
  52% would need a profit of ₹12.48 on the same outlay. The gap between the ₹36 taken and the ₹24 given up is a flat ₹12, and 12/24 is one half exactly.
• (d)
  48% is the near miss for anyone who compounds carelessly. Both ratios here are exact — 36/30 = 1.20 and 1000/800 = 1.25 — and their product is 1.50, so nothing shaves the answer below 50.

Two separate gains are stacked here, and they multiply rather than add.

The first is the honest mark-up: bought at ₹30, sold at ₹36, a factor of 1.20. The second is the short weight: he charges for 1000 g and delivers 800 g, so each rupee of stated cost buys only 0.8 kg, a factor of 1000/800 = 1.25.

Multiply them: 1.20 × 1.25 = 1.50, a 50% gain. Adding 20 and 25 to get 45 is wrong, because the weight gain applies to the already marked-up price.

Key facts

• Profit percentage is computed on cost price, never on selling price.
• A false weight of w grams sold as 1000 g multiplies the gain by 1000/w.
• Here the 800 g handed over cost 0.8 × ₹30 = ₹24 and fetched ₹36.

Common traps

• Costing the whole kilogram at ₹30 and reporting 20% profit
• Adding 20% and 25% to reach 45%
• Dividing the ₹12 profit by the ₹36 selling price and reporting 33.3%

No directly related past PYQ was found.