The Al Gore Rhythm

Here is a really interesting trick to multiplying large numbers in your head, and quickly.....

"Here’s the “mystery algorithm” for 26 * 31, or any other set of two-digit numbers. Keep in mind that the description is much longer than the problem should take. After a little practice, it should take no longer than 10 seconds to do a problem like this in your head."

Read the method here

"....One more thing. Although this method beats the pickles out most methods, doing something as simple as 26 x 31 only requires that you multiply 26 by 3 in your head (any 3rd grader should really be able to do that, if we didn’t treat them like simps), stick a 0 at the end. That’s 780. Mentally add 26 to that, and Bob’s your uncle." MY SIDE NOTE: To use this trick when the second number (31) has a ones digit greater than one (say 37, rather than 31), simply multiply 26 by the ones digit number (7), and then add that number to your original 780. ;)

Read more....