Magic Number 1089: Choose a three-digit number where the first and last digits differ by at least 2. Reverse the digits and subtract the smaller from the larger. Add the result to its reverse. The answer will always be 1089! For example, if you choose the number 634, the calculation would be: 634 - 436 = 198, 198 + 891 = 1089.

Multiply by 9: To multiply any number by 9, hold out all 10 fingers, and lower the finger that corresponds to the number you're multiplying by. The number of fingers before the lowered finger is the tens place, and the number of fingers after is the ones place. For example, to multiply 6 by 9, hold out both hands, and lower the 6th finger on your left hand. You'll have 5 fingers before and 4 fingers after, giving you an answer of 54.

Add to Zero: Choose any two-digit number, add its digits together, then subtract that sum from the original number. The result will always be a multiple of 9, and if you add the digits of the result together, the sum will always be 9. For example, if you choose the number 78, the calculation would be: 78 - (7 + = 63, which is a multiple of 9. 6 + 3 = 9.

Want to learn more follow me at SMASH Maths