[email protected]

My son (14) asked how this works. He tried several times to stump them,
with no luck. He wanted to know he mathematical method for "guessing" the
numbers. I'm sure it's a very simple and logical process, but I have no answer.
Can anyone help? Thanks.

Wendy (mom to Alex, wife to Andres) in Homestead, FL


[Non-text portions of this message have been removed]

Joyce Fetteroll

On Jul 9, 2006, at 3:08 PM, wenrom31@... wrote:

> My son (14) asked how this works. He tried several times to stump
> them,
> with no luck. He wanted to know he mathematical method for
> "guessing" the
> numbers. I'm sure it's a very simple and logical process, but I
> have no answer.
> Can anyone help? Thanks.

Boy that message has been shuffling about the internet for a few days!

It's the magic of our base 10 system :-)

Basically what you're doing is eliminating the second digit and then
subtracting the first digit from 10 times the first digit which
always give 9 times the first digit. On the Egyptian chart at the
end, all the multiples of 9 always have the same symbol next to them.

Algebraically it goes like this ...

If a number looks like ab, it would be represented algebracially as:

10*a + b.

So for:

12 then a=1 and b=2 so 12=10*1 + 2
37 then a=3 and b=7 so 37=10*3 + 7
82 then a=8 and b=2 so 82=10*8 +2

In the first step of the game they ask you to add a and b together.
And then they tell you to subtract that number from the original
number. That's just a way of eliminating the last digit so all
problems turn into:

10*a + b - (a+b)

rearranging, you can see that the b part of every 2 digit number gets
eliminated:

10*a - a + b - b

So all problems turn into either 10-1, 20-2, 30-3, 40-4 ...

10*a - a = 9a

10*1 - 1 = 9*1 = 9
10*2 - 2 = 9*2 = 18
10*3 - 3 = 9*3 = 27

and so on. So all two digit numbers are turned into 9 times the first
digit of the number.

Joyce



[Non-text portions of this message have been removed]

Sandra Dodd

Two things: The site they're talking about is this:

http://www.learnenglish.org.uk/games/magic-gopher-central.swf

Joyce's explanation is great *except* I think what she failed to say
to calm math-phobes is that the "Egyptian chart" changes each time.
So if a player is thinking that the cartoon gopher is choosing from
all those different symbols and numbers, no. The reason different
symbols show different times is that the program changes (either in a
sequence or randomly) and all the numbers that are NOT multiples of
nine (which are never going to be your final answer) are just there
for looks, to confuse you. And each time whatever picture is next to
9, 18, 27, 36, 45, 54, 63, 72, 81 and 90 will be the same picture.
The rest are probably lined up in ways that keep one from being right
next to another.

Scratch that, because I just looked and on this particular shuffle,
11, 12 and 13 all have the same symbol. That doesn't matter, because
they're not going to be right answers. I'm going to go through the
screens again. Next time, they have different symbols. So yeah,
it's just for purposes of distraction and to make it seem magic.
It's not that 9 is a jug or an arrow, it's that whatever 9 is is what
the gopher will show you, and that will change each time you play.

Sandra

[email protected]

Thank you Joyce and Sandra. :-)

Wendy


[Non-text portions of this message have been removed]