well guys,, now i'll share some tricks for solving math problem that i got when i was a student. learn the tricks to amaze and impress others as you mentally solve tough math problem.
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- Square number ending in 5
85 x 85 = 7225
Step 1. Multiply the firs digit by the firs digit plus one: 8 x (8+1) = 72
Step 2. Write the number 25 next to the number frop the first step : 7225
25 x 25 = 625
Step 1. 2 x (2+1) = 6
Step 2. 625
- Multiply two digit number by 11
Step 1. Add both digit of the two digit number: 5 + 3 = 8
Step 2. Place the result between both digits: 583
59 x 11 = 649
Step 1. 5 + 9 = 14
Carry the 1 when the result is greater than 9: 5+1 = 6
Step 2. 649
- Multiply even number by 5
Step 1. Divide the even number by two: 242/2 = 121
Step 2. Put a 0 at the end of the result: 1210
- Multiply between 10 and 19
Step 1. Add the larger number to the rightmost digit of the other number: 18+7 = 25
Step 2. Put a 0 at the end of the result from step 1: 250
Step 3. Multiply the rightmost digits of both original numbers: 8 x 7 = 56
Step 4. Add step 2 and step 3: 250+56 = 306
- Divide by 5, 50, 500, etc.
52/5 = 10.4
Step 1. Multiply the number being divided by two: 52 x 2 = 104
Step 2. Shift the number from step 1 by one decimal point: 10.4
482/50 = 9.64
Step 1. 482 x 2 = 964
Step 2. Shift the number from step 1 by two decimal points (for dividing by 500 shift by three decimal points): 9.64
