RE: Mental Calculation Show: Arthur Benjamin, The Mathemagician
October 31, 2016 at 2:18 pm
(This post was last modified: October 31, 2016 at 2:19 pm by Kernel Sohcahtoa.)
(October 31, 2016 at 12:25 pm)Fireball Wrote: I used to do mental math back when we had slide rules. One needs to be sure of the magnitude of the number when calculating, in order to operate the slide rule properly. After a while, it's just easier to do the math in your head. I could multiply a pair of two digit numbers faster in my head than most people could on a calculator. I haven't had a need for that in awhile, so it takes me longer to do it. Never heard of these books, but as long as I have a calculator, I'm OK. He's certainly entertaining!
Cool post, Fireball. I used to be into mental calculation. In particular, I enjoyed doing big multiplications. For example, I am able (naturally with lots of practice) to multiply two distinct five digit numbers in a minute or less (I'm a bit rusty now though); however, I need to see the numbers in order to do it fast. While Benjamin uses left to right calculation and verbal mnemonics to store his intermediate calculations, I used photo mnemonics to store some of the digits I obtained via cross multiplication. If anyone is interested to learn how to multiply four or five digit numbers, just let me know and I'd be more than happy to make a video; IMO, it is a nice addition to any magician's/mathemagician's bag of tricks . With that said, I'm glad that people have enjoyed this.
