💰 SSC CGL – Profit, Loss & Discount (Tips, Shortcuts with Examples)

 

💰(Tips, Shortcuts with Examples) – Profit, Loss & Discount

These methods are frequently used by toppers to save time in the exam.

🧠 SSC CGL EXAM STRATEGY

✔ Use ratio method instead of long %
✔ Always check successive discount formula
✔ Convert % to fractions mentally
✔ Avoid CP–SP equation unless required
✔ Practice mixed questions (Profit + Discount)

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🔹 BASIC TERMS (1-line clarity)

• CP = Cost Price

• SP = Selling Price

• Profit = SP − CP

• Loss = CP − SP

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✅ 1. Profit / Loss Percentage (Golden Formula)

$$\text{Profit \%} = \frac{\text{Profit}}{\text{CP}} \times 100$$ $$\text{Loss \%} = \frac{\text{Loss}}{\text{CP}} \times 100$$

Example

CP = ₹400, SP = ₹460
Profit = 60
Profit % = (60/400)×100 = 15%

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✅ 2. Direct SP–CP Conversion Shortcut

• Profit p% → SP = CP × (100+p)/100

• Loss p% → SP = CP × (100−p)/100

Example

CP = 500, Profit = 20%
SP = 500 × 120/100 = ₹600

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✅ 3. When SP is Given & CP Asked (SSC Favourite)

• Profit p% → CP = SP × 100/(100+p)

• Loss p% → CP = SP × 100/(100−p)

Example

SP = 660, Profit = 10%
CP = 660 × 100/110 = ₹600

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✅ 4. Quick Ratio Method (Very Fast)

Instead of %, convert to ratio.

• 25% profit → CP : SP = 4 : 5

• 20% loss → CP : SP = 5 : 4

Example

SP = 800, Loss = 20%
CP : SP = 5 : 4
CP = (5/4)×800 = ₹1000

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✅ 5. Successive Profit / Loss Shortcut

For successive changes a% and b%:

$$\text{Net \%} = a + b + \frac{ab}{100}$$

(use + for profit, − for loss)

Example

Profit 20% and then loss 10%
Net = 20 − 10 − (20×10)/100
= 8% profit

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✅ 6. Marked Price (MP) & Discount Basics

$$\text{Discount} = MP − SP$$ $$\text{Discount \%} = \frac{\text{Discount}}{MP} × 100$$

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✅ 7. Discount Shortcut

If discount = d%
SP = MP × (100−d)/100

Example

MP = 2000, Discount = 25%
SP = 2000 × 75/100 = ₹1500

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✅ 8. Successive Discounts (SSC Favourite Trick)

For two discounts a% and b%:

$$\text{Net Discount \%} = a + b − \frac{ab}{100}$$

Example

20% and 10% discount
Net = 20 + 10 − 2 = 28%

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✅ 9. Profit After Discount (Very Important)

If:

• Marked up by x%

• Discount given y%

Net Profit % =

$$x − y − \frac{xy}{100}$$

Example

Marked up 40%, Discount 10%
Profit = 40 − 10 − 4 = 26%

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✅ 10. False Weight Trick (SSC Classic)

Profit % =

$$\frac{\text{Extra weight}}{\text{Actual weight}} × 100$$

Example

Sells 900 g as 1 kg
Profit = 100/900 × 100 = 11⅑%

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🔥 MOST COMMON % → FRACTION (MEMORIZE)

%	Fraction
10%	1/10
20%	1/5
25%	1/4
33⅓%	1/3
50%	1/2