Ten class (10th)mathematics tricks
1. Multiplying by 11 (Two-digit Numbers) Trick: For a number like 52: Add the digits: 5 + 2 = 7 Place the result in the middle: 52 × 11 = 572 (If the sum is 10 or more, carry over) 2. Square of a Number Ending in 5 Trick: For a number like 75: Take the first digit(s): 7 Multiply it by (7 + 1): 7 × 8 = 56 Add 25 at the end: 75² = 5625 3. Quick Percentage Calculation Trick: Find 10%, 1%, and build from there. E.g., 18% of 250 → 10% = 25, → 1% = 2.5 → 8% = 2.5 × 8 = 20 → Total = 25 + 20 = 45 4. Squaring Numbers Close to 100 Trick: E.g., 103² = 100² + 2×100×3 + 3² = 10000 + 600 + 9 = 10609 5. Divisibility Rule for 7 Trick: Double the last digit, subtract from the rest. If result is divisible by 7, so is the number. E.g., 203 → 20 - 6 = 14 → Yes! 6. Product of Two Numbers with Same Tens and Ones Adding to 10 Trick: E.g., 43 × 47 Tens = 4 Ones = 3 and 7 (adds to 10) → 4 × (4 + 1) = 20 → 3 × 7 = 21 → Answer = 2021 7. Multiplying Two-Digit Numbers Ending in 1 Trick: E.g., 21 × 31 → (20 + 1) × ...