Finding 55 percent of a number

1. Choose a 2-digit number.
2. Multiply the number by 11. (Add digits from right to left - see examples).
3. Divide by 2.
4. Move the decimal point one place to the left.

   Example:

1. If the number selected is 81:
2. Multiply by 11: 11 x 81 = 891
   right digit is 1
   next digit to left is 1 + 8 = 9
   last digit to left is 8
3. Divide by 2: 891/2 = 445.5
4. Move the decimal point one place to the left: 44.55
5. So 55% of 81 = 44.55.

   See the pattern?

1. If the number selected is 59:
2. Multiply by 11: 11 x 59 = 649
   right digit is 9
   next digit to left is 9 + 5 = 14 (use the 4 and carry 1)
   last digit to left is 5 + 1 = 6
3. Divide by 2: 649/2 = 324.5
4. Move the decimal point one place to the left: 32.45
5. So 55% of 59 = 32.45.