Percentage kab kab calculate karna padta hai?
Percentage ek universal concept hai — school se lekar business tak har jagah use hota hai:
- Exam marks: 450 out of 600 — kitna percentage?
- Shopping discount: ₹800 par 30% off — kitna bachega?
- Salary hike: ₹25,000 se 15% increase — naya salary?
- GST calculation: Amount par 18% GST — total kitna?
- Profit margin: Cost ₹100, sell ₹140 — margin %?
Common percentage formulas
| Calculation | Formula | Example |
|---|---|---|
| X% of Y | (X/100) × Y | 30% of ₹800 = ₹240 |
| X is what % of Y | (X/Y) × 100 | 450 out of 600 = 75% |
| % increase | ((New-Old)/Old) × 100 | ₹25k→₹28k = 12% increase |
| % decrease | ((Old-New)/Old) × 100 | ₹100→₹85 = 15% decrease |
Board exam percentage
CBSE percentage = Total marks obtained / Total max marks × 100. Agar practical marks alag hain — dono add karein numerator aur denominator mein.
Discount ke baad price calculate karna?
Final price = Original × (1 - discount%/100). Example: ₹1000 par 25% off = ₹1000 × 0.75 = ₹750.
Successive discounts ka kya matlab hai?
Pehle 20% phir 10% discount: ₹100 → ₹80 → ₹72. Total 28% discount (not 30%). Successive discounts add nahi hote — multiply hote hain.