To easily multiply any 2digit number by 11, you should use the 11rule. For instance, the 2digit number to be multiplied by 11 is 54. First, separate the two digits. Afterwards, add 5 and 4 together (5+4=9). Put the sum between the 2 numbers, and you’ll get 594. So 11 multiplied by 54 is equal to 594. 
But if the sum is greater than 9, you only put the "ones" digit in between the numbers and carry over the "tens" digit – example: 11 x 57 ... 5__7 ... 5+7=12 ... put 2 between the numbers and add 1 from the 12 to 5 in order to get 6 for a result of 627 ... 11 x 57 = 627
These rules were made from patterns and generalizations. For more, it’s just a matter of going to MathComplete.Com since this site is always updated with the newest math tricks available. This means you can regularly check this site for updated math tricks.
