Now let us take a look at 63 x 43. What is special about this? The left hand digits add up to 10 and the right hand digits are the same.
The was to do it is multiply the left hand digits and at the left hand digit to the answer. This will be the two left and digits to the answer. The right hand digits? Simply multiply the digits together. Remember to add a 0 if the answer is a single digit.
In the above example: Right hand digits = (6 x 4) + 3 = 27.
Left hand digits = 3 x 3 = 09
Thus the answer to 63 x 43 = 2709.
QED (Quite Easily Done).
