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Brian Foley ⁽⁶³⁹⁾ United States

Brian Foley

Magic and Learning

Multiplying by Nine with the Finger Method

Posted Monday, November 24, 2008 (363 days 17 hours ago.) Viewed 346 times.

Can you do the nine-times tables on your fingers?

When you learn how, you'll never have to stare at the multiplication tables charts for nine again. The best part is, you only need to be able to count in order to learn this!

And if you practice using the finger method, you'll be a whiz at multiplying any digit by nine, and never have to "guess" and hope you're right again.

You can learn it now, in a few simple steps that you'll never forget. But you must remember that it is not meant to be a crutch. You must practice it a lot in order to get it to the point where you don't need to do it on your fingers every time you want to multiply by nine.

At the end of the article, you'll find a great, free resource where you can find a fun way that will make you love to practice it, and it will also teach you why the method works.

Let's get down to multiplying:

First, you have to number each of your fingers. With your hands palms down, thumbs almost touching, start from the left and call your L. small finger, "one." The L. ring finger is "two," the L. middle finger is "three," etc. until you get to the R. pinky, which is "ten."

That was easy!

Now, to multiply any digit by 9, you simply bend the finger that has that number inward. In other words, if you were to multiply nine by three, you'd bend the "three" (that's the L. middle finger). Bend it inwards, beneath your hand.

Notice the number of fingers on the left of the finger that's bent. There should be two of them. That's how many tens there will be, making the answer, "twenty-something."

Next, notice the how many fingers are on the right side of the finger that's bent. There should be seven of them. That's how many units there will be, making the answer, "twenty-seven."

That's it. Your done!

Warning! - This should not be used as a "trick." Don't make it a crutch. Practice it until you know the "nines-times-tables" by heart. If you still need to use your fingers after a day or two to practice, then you really haven't practiced enough.

There is a "master method" for using your fingers to learn to multiply. You only need one method for all the numbers from 6-9, so you don't have to learn a bunch of different "multiplication tricks."
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Brian Foley (a.k.a. "Professor Homunculus") is the creator and web manager of Math Mojo and TheMath Mojo Chronicles. He's presented his Math and Magic programs at schools, corporations, and other facilities throughout the U.S. and Europe.

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Memorizing the Multiplication Tables to 20 - That's Just Crazy!

Posted Sunday, November 23, 2008 (364 days 14 hours ago.) Viewed 1,474 times.

Do you have a child who needs a confidence-boost in school? Imagine if your child knew the multiplication tables up to 20. It would make him or her seem like a genius compared to most school children who have problems even remembering 7x 8!

If you are like most people, you probably think that memorizing the times tables to twenty would be a heck of a chore. It would! It would be crazy!

I feel sorry for anyone who's already done that when they read ahead and learn the method to get the answer to any multiplication problem with whole numbers between 10 and 20, fast, with no need for memorization. They would have saved weeks of boring, rote memorization if they used this method instead.

Here's how you do it:

Let's say you are multiplying 12 x 17.

Step 1) Add the ones column of either of those numbers to the other number. In this case you could add either 7 + 12 or 2 + 17. (Both would give you the same result, namely 19). Put a zero after it, to get 190.

Step 2) Get the product of the last digits of each of the original numbers (that would be 2 x 7, which would give you 14).

Step 3) Add the two numbers you got. In this case that would be 190 + 14. You'd get 204, and you'd be done, because 12 x 17 = 204.

That's how easy it is, and it works for any numbers between 10 and 20!

Try 19 x 14.

1) 19 + 4 = 23. 23 with a zero at the end is 230.

2) 9 x 4 =36

3) 230 + 36 = 266, which is the correct answer. Piece of cake!

Please, please, please don't ever write anything down when you do this! It wlll defeat the whole purpose of this method. Writing down things that a child's mind should be able to do is like training yourself to use crutches when you don't need them. The whole point of this is to trust your brain, and learn to do simple math mentally.

Here are some more examples. Once you have practiced them, you should become fast enough to amaze anyone, especially an elementary school teacher. A third-grader should be able to do these with ease in a short time, and become the "Einstein" of his or her class.

18 x 13

15 x 16

19 x 18

17 x 14

12 x 16

You may come across instances where you will have to carry. You will automatically understand how to do that if you pay attention.

Remember, you are trying to boost confidence, and you can't do that unless you have the basics down. With the basic multiplication tables "in your bones," this way to multiply numbers up to 20 can be a "reputation-maker."

Of course, if you or someone you know (your child or student, maybe?) hasn't totally masteredthe "multiplication tables," the above method won't do you much good, will it? You'll be happy to know that there is a fool-proof, easy way to teach or learn the basic times-tables in minutes, and it's even easier than the the method for multiplication of 10 through 20. You can learn about it at Learn to Multiply.

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"The Raven" for Bloggers

Posted Tuesday, November 18, 2008 (1 year 4 days ago.) Viewed 1,148 times.

This is my own parody. A work in progress. So far it's untitled.

Once, before the midnight deadline, helpless, hunting for a headline,
For one of my quaint and curious blog posts; for some pithy quote.
As my E-books I was hyping, suddenly I noticed typing,
as if someone had been Skype-ing, Skype-ing me a threatening note.
"'Tis my editor", I muttered, "Skype-ing me a threatening note".
Only this, it will connote.

Oh, it was in late October, and I was but scarcely sober,
And I'd knocked the bottle over, spilling Scotch upon my coat.
How I hankered for a cuppa', vainly craving picker-upper
Wishing I had eaten supper, 'ere searching for that anecdote -
For that magic, muse-inspired, piercing, poignant anecdote -
Stuck somewhere within my throat.

And the startling stark insipid presage of each IM message
Dinging, ringing with that harried harping harridan-like note
Irked me now, and to distraction, so that my annoyed reaction,
Was a strange and sad attraction, attraction to the news it bode.
Some silly, strange and sad attraction, attraction to the news it bode.
This odd thought it did promote.

Presently, my interest got me; Mute the call? Oh no, no not me,
"Damn" I said, (or "Dammit," truly I must say, lest I misquote)
And, in fact, I was just wiping dust from off the keyboard, typing
A late reply unto the Skype-ing, Skype-ing in form of IM note.
Scarcely had I sent a reply, when there came a return note -
Nothing much, did it denote.

Quizzically I eyed the missive, imagining intent derisive.
Querrying, tweeting tweets no blogger ever dared to tweet before
But the blogosphere was silent, not so much as one repliant
And it nearly made me violent, that no soul a tweet had twote.
This I rued - that not a living soul a single tweet had twote.
Truly this had got my goat.

Read more about Edgar Allen Poe's masterpiece, "The Raven" and other parodies of it at:
http://best.poem.ever.com/

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Little Sairy Palin

Posted Tuesday, November 18, 2008 (1 year 4 days ago.) Viewed 25 times.

This is a parody the poem "Little Orphant Annie," by Charles Whitcomb Riley.

LITTLE Sairy Palin's come to the Lower Forty-eight,
An' teach us fambly values, an' denyin' Troopergate.,
An' shoo the lib'ruls outta Washington and say who's patriotic,
An stoke the rage of racist swine, an' other things psychotic :
An' all us other citizens, when the debatin' stuff is done,
We set around the YouTube, where we have the mostest fun
An' list'nin' to the witch-hunt, 'at Sairy tells about
An' there be libuh-ruls, you betcha'!
Ef you
Don't
Watch
Out!

Wunst Obama sat in church where Reverend Wright said prayers,
An' palled around with terrorists, like that weather-guy Bill Ayers,
An' Sairy had paroxysms, and McCain near bust a gut,
An' they forgot Sairy's anti-semite pal, and that secessionist wing-nut.
An' they blamed the Hollywood elite and lib'rul mainstream press,
An' ignored that Johnny Warbucks voted with Bush each time, I guess;
But ad hominem invective is all they ever spout,:--
An' there be social-ists, you betcha'!
Ef you
Don't
Watch
Out!

An' one time Little Sairy wud allus laugh and wink,
An' tell any goon who'd listen, how all the lib'ruls stink.
An' wunst, when she's on CBS, with Katie Couric there,
She didn't know her ass from dirt, and said she didn't care!
An' thist as she high-heeled it, and her handlers had her hidin',
They handed her her ass agin', in her de-bacle with Joe Biden,
She turned the independents off, 'fore she knowed what she's about!
An' there be terror-ists, you betcha!"
Ef you
Don't
Watch
Out!

An' Little Sairy says that whut's black is really white,
An lies are truths, that she loves Jews, and wrong is really right.
An' you hear the 'pocrisy in her words, an' nonsense in her action,
An' no wonder why the 'publicans can't get no satisfaction,
She'd best re-read her good book that she says she loves so dear,
Instead of preaching anger, and rage and hate and fear.
An' hep' the honest, thoughtful ones 'at clusters all about,
'Cause the Demo-crats'll git her!
Ef she
Don't
Watch
Out!

You can read a little about the story of this poem, as well as hear an audio-file of the author reading it a:

http://www.squidoo.com/SairyPalin

You can also read the original poem, "Little Orphant Annie" there.

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