On which value is profit percentage calculated?

Profit or loss percentage is calculated on cost price unless the question says otherwise.

What is the difference between discount and loss?

Discount is calculated on marked price, while loss is calculated by comparing selling price with cost price.

Profit and Loss — Formulas, Shortcuts, and Worked Examples | TNPSC, SSC, Bank

Quick Concept Summary

Profit and loss questions test whether you can keep four prices separate: cost price, selling price, marked price, and discounted price. Most mistakes come from mixing those bases.

Key Terms

CP: Cost Price
SP: Selling Price
MP: Marked Price
Profit: SP - CP
Loss: CP - SP

Worked Examples

Example 1: Direct profit

An item is bought for Rs. 800 and sold for Rs. 920.

Profit = 920 - 800 = 120

Profit% = 120/800 × 100 = 15%

Example 2: Find selling price

Find SP if CP is Rs. 1,250 and profit is 12%.

SP = 1250 × 112/100 = 1400

Example 3: Marked price and discount

An article marked at Rs. 2,000 is sold at 15% discount.

SP = 2000 × 85/100 = 1700

Discount vs Loss

Discount	Loss
Based on marked price	Based on cost price
Offered before sale	Known after comparing SP and CP
Can still lead to profit	Always means SP is below CP

Shortcuts

If profit is p%, use multiplier (100+p)/100
If loss is l%, use multiplier (100-l)/100
Two discounts a% and b% combine as a + b - ab/100

Practice Questions

1. CP = Rs. 600, SP = Rs. 690. Find profit%. 2. An item sold at 20% loss brings Rs. 960. Find CP. 3. MP = Rs. 1,500 and discount = 12%. Find SP. 4. A trader marks goods 25% above CP and gives 10% discount. Find profit%. 5. Two successive discounts of 20% and 10% equal what single discount?

Common Mistakes

Calculating profit percentage on selling price
Treating discount as loss
Forgetting the difference between marked price and cost price

Revision Checklist

[ ] CP, SP, MP distinction clear
[ ] Profit and loss formulas memorised
[ ] Discount multiplier practised
[ ] Successive discount questions revised