Way way OT but someone might know

On Thu, 11 Jun 2015 13:44:43 -0700, Gene Wirchenko
wrote:


Yesterday, my student that I tutor in math had a misunderstanding
on 10 / 0.5. The answer is not 5 as he thought. Many other people
would make the same mistake, but that does not make it correct.


Since neither you nor anyone else stated the correct answer, I'll
throw it in. It's 20.

And yes, many people would think 5 is correct--perhaps even more
people than would know the correct answer.

On 06/11/2015 05:27 PM, pjp wrote:

[snip]

There's a very simple math equation that "proves" 2 = 1. Can't remember
exact formula you started out with (was something like x2 + y2 = (x + y)
2 - the "2" represents squared). Was only about four lines for proof but
one had to notice there was a divide by zero in it that invalidated what
followed. Saw that in grade 10 and basically freaked till noticed the
problem, most would never see it.

Anyone remember it more exactly?


As to division by 0:

Consider any (nonzero) numbers a and b

a / b = c
b / a = d
c * d = 1

or, all on one line

(a / b) * (b / a) = 1

That is, with the operands reversed, the result is the reciprocal

4 / 2 = 2
2 / 4 = .5
2 * . 5 = 1

With 0

0 / 2 = 0

so, 2 / 0 should be the reciprocal of 0, which is infinity. Infinity
isn't a number. In some ways, 0 isn't either.

Perhaps 0 not being a number explains the oddity of being able to move
east from anywhere but not at the pole (the distance around the earth
becomes 0 there).

0 / 0 is still an oddity. Is it infinity (like every other number
divided by 0) or is it 1 (like every other number divided by itself)?

--
Mark Lloyd
http://notstupid.us/

"The Devil...clutched hold of the miserable young man...and flew off
with him through the ceiling, since which time nothing has been heard of
[him]." [Martin Luther]

Mark Lloyd wrote:

[snip]

Yesterday, my student that I tutor in math had a misunderstanding
on 10 / 0.5. The answer is not 5 as he thought. Many other people
would make the same mistake, but that does not make it correct.

Sincerely,

Gene Wirchenko


How would someone get 5 for that?


Interpret the problems as (0.5 or 50%) of 10 would seem to be the most
likely reason.

Not understanding the outer/inner product method
i.e.
instead of (10/1)/(5/10) = 100/5 = 20
seeing it as top product/bottom product = 50/10 = 5

Other reasons - left glasses or contacts at home g



--
...winston
msft mvp consumer apps

Mark Lloyd wrote:
On 06/11/2015 02:21 PM, Ken Blake wrote:
On Thu, 11 Jun 2015 14:00:55 -0500, Mark Lloyd
wrote:


There's also "if 1 and a half chickens lay 1 and a half eggs in 1 and a
half days, how many eggs will 9 chickens lay in 9 days?"


54

If 1 and a half chickens lay 1 and a half eggs in 1 and a half days,
then 1 chicken can lay 1 egg in 1 and a half days.

Multiply the day and a half by six to make 9 days, and that same
chicken can now lay 6 eggs.

If one chicken can lay six eggs (in any amount of time), then 6
chickens can lay 54 eggs.


That's right. I've seen some people who refuse to do anything arguing
about half-chickens being unable to lay eggs. The problem is simple when
you just use math.


Math:
9 x [(1/1.5 )= (x/9))] solving for x yields '6' then 9 x 6 = 54

--
...winston
msft mvp consumer apps

In alt.windows7.general message kd8jna5o5bsbc0ldqnpm0b6figur8lhhjj@4ax.
com, Thu, 11 Jun 2015 08:23:47, Ken Blake posted:

Other examples: Amsterdam, Madrid, Lisbon, Philadelphia, Miami,
Boston, Denver, Chicago O'Hare, Chicago Midway, Heathrow, LAX, San
Diego, Nice, Buenos Aires Aeroparque. I *think* those are all within
city limits.

Heathrow is not within a City. It is, however, within the Mayoralty of
Boris. London City Airport is not within the City of London, but that
City and the City of Westminster are within the Mayoralty.

--
(c) John Stockton, Surrey, UK. Turnpike v6.05 MIME.
Web http://www.merlyn.demon.co.uk/ - FAQish topics, acronyms, & links.

On Fri, 12 Jun 2015 10:28:28 -0700, Stormin' Norman
wrote:


On Thu, 11 Jun 2015 17:22:13 -0700, Stormin' Norman
wrote:

On Thu, 11 Jun 2015 17:10:49 -0700, Ken Blake

Are you the same Ken Blake as Ken Blake, MVP? I have always assumed
so, but that might be a mistake.


Yes, I'm a Microsoft MVP. I've been one since October 2003. There are
three of us here--one other MVPs and one ex-MVP.

I asked because I have seen recent posts from you in other groups with
your name and MS credentials, but in this group you omit the
credentials from your name. Just confirming you are one in the same
person.


If I've omitted the "credentials" here, it was an accident. I'll look
into it.


Ahh, what it must be like to have a simple, two syllable name


Years ago I worked with someone with a simple, four letter, two
syllable name: Fn Ng. It's probably a common name in China, but it was
odd enough to me that I never forgot it.

On 06/12/2015 02:00 PM, Wolf K wrote:

[snip]

When it comes to language, how most people use it is what's right.


I suppose most people would follow that rule.

That is, they're doing it that way just because other people do. Then
THOSE people are doing it in a way that other people do. Ad nauseum...

There's nothing "right" about that. Try doing your own thinking.

--
Mark Lloyd
http://notstupid.us/

"The Devil...clutched hold of the miserable young man...and flew off
with him through the ceiling, since which time nothing has been heard of
[him]." [Martin Luther]

On Fri, 12 Jun 2015 17:52:24 -0400, Wolf K wrote:

On 2015-06-12 4:34 PM, Mark Lloyd wrote:
There's nothing "right" about that. Try doing your own thinking.

Dear, dear, getting snarky, are we? Don't do that again, or I'll snark
right back at you.

It seems to me that you, Wolf, were doing your own thinking.
That is Mark's problem.

But I'm getting tired of this willy waving contest anyway.

--
Wildman GNU/Linux user #557453
My hands are in the air like I just do not care!