Multiplying a 2-digit number by 594

1. Select a 2-digit number .
2. Multiply it by 6.
3. If the product is 2 digits, subtract 1:
   X X _ _
   Then subtract the product from 100:
   _ _ X X
4. If the product is 3 digits, add one to the first digit
   and subtract the result from the product:
   X X X _ _
   Then subtract the last two digits of the product from 100: _ _ _ X X

   Example:

1. The 2-digit number chosen to multiply by 594 is 16.
2. Multiply by 6: 6 x 16 = 60 + 36 = 96
3. Subtract 1: 96 - 1 = 95: 9 5 _ _
4. 100 - product: 100 - 96 = 4: _ _ 0 4
5. So 594 x 16 = 9,504.

   See the pattern?

1. The 2-digit number chosen to multiply by 594 is 92.
2. Multiply by 6: 6 x 92 = 540 + 12 = 552
3. 1st digit + 1: 5 + 1 = 6
4. Subtract 6 from product: 552 - 6 = 546:
   5 4 6 _ _
5. 100 - product's last 2 digits: 100 - 52 = 48:
   _ _ _ 4 8
6. So 594 x 92 = 54,648.