Math Shortcuts: Quick Calculation Tricks for All Exams

Speed Up Your Math Calculations

Time management is crucial in competitive exams. These shortcuts will help you solve math questions faster across all exam types.

Percentage Shortcuts

• To find 10% of any number, just move the decimal one place left
• 5% = Half of 10%
• 15% = 10% + 5%
• 20% = 10% × 2
• 25% = One-fourth of the number

Multiplication Tricks

• Multiply by 11: Add adjacent digits (e.g., 23 × 11 = 253)
• Multiply by 5: Divide by 2 and multiply by 10
• Multiply by 25: Divide by 4 and multiply by 100
• Multiply by 99: Multiply by 100 and subtract the number

Division Tricks

• Divide by 5: Multiply by 2 and divide by 10
• Divide by 25: Multiply by 4 and divide by 100

Square Shortcuts

For numbers ending in 5: (First digit × Next digit) and append 25

Example: 25² = 2 × 3 = 6, append 25 = 625

Important Formulas

• Time and Work: If A does work in x days and B in y days, together they finish in xy/(x+y) days
• Ratio and Proportion: If a:b = c:d, then ad = bc
• Average: Sum of all numbers / Count of numbers

Practice Tips

1. Memorize tables up to 20
2. Learn squares up to 30 and cubes up to 12
3. Practice mental calculations daily
4. Use approximation for complex calculations
5. Learn estimation techniques for data interpretation