Logic Challange

Started by Darla5 pages

$10

$20

A-ha! Two different answers already... well, I'll let people argue it out...

BTW, obviously some COUNTING is involved here, but it is basic enough for it not to really be a maths problem.

no, you lose the first $10 the second time you buy it, so you only make $10 overall. right, ush?

have to go to 2 rehearsals now, sees ya tomorrow!

Bye Darla! Thanks for playing!

Well, I'd better let others guess before I blow it all...

You buy it so you are -$70, you sell for $80 so +$10,
You buy for $90 so are -$80, you sell for $100 so +$20.

oh crap, just ignore me, i told you i was no good at these. dunno what i was thinking, sorry corran.

This could all take a while... there is a third commonly given answer, btw (that I got from Julie when I mailed her this one the oither day)

Originally posted by Darla
oh crap, just ignore me, i told you i was no good at these. dunno what i was thinking, sorry corran.
I could never ignore you, I like Vampires - especially female ones.

No wait, please don't run away I don't want to hurt you, I only want to be your friend. 😈

I'll just see if any others want to take a stab tonight...

it's 10..

Ah! Another vote for 10! The fun continues!

Any other guesses?

this one was sent to me by michael again:

you have 1 000,
you add 40
you add 1 000
you add 30
you add 1 000
you add 20
you add 1 000
you add 10

what's your result?

and this is maths, finti, I know

EDIT: it's a stupid one, but this was actually asked in a game, where you had to answer quick, she (hehehe, guess "you stupid woman!" is true) got it wrong

Errr... one at a time I think, yerss.

"I buy a painting for $70"

-$70

"sell it for $80"

+$10

"buy it for $90"

-$80

"then sell it for $100"

+$20

"How much profit do I make?"

+$20

"And despite how it looks it is not a maths problem!"

Are you sure?

Yes, Raz, because it is only adding very basic numbers! Which i thought was pretty obvious. People that get it wrong get it wrong due to logical flaws; solving it has almost nothing to do with mathematical ability. No-one who gets it wrong has their maths at fault.

I've always associated mathematical ability with logic ability. You can't really do a maths course without good logic, although crap arthimetic will probably not hinder you. *puts hand up*

Yes, maths IS logical; I would have no problem associating maths problems with logic. But logic is not necessarily maths, and though my question involves basic addition and subtraction the logic involved is different.

You are right, of course, and the reason you didn;t see the seperation is because you got it right at once- as I said when I set it, some people do that and never see the problem.

The question tricks you if you go through it step by step- or it CAN trick you, if you start thinking about profit and loss rather than pure numbers. Darla and Mah- intelligent people both- both made the same error of thinking of it like this:

I make $10 when I first sell it, lose $10 when I buy it back, and then make $10 when I sell it again, for ten dollars profit.

This way of thinking means you have accidentally used the same number twice.

Likewise Julie's reasoning (she said break even), which is that you make $10 in selling for $80 what you bought for $70, then you lose $20 buying for $90 what you originally played $70 for, and then make ten back on the final sale for an even break.

Both ways seem very logical for anyone thinking of it that way but invovle the same errors of using the numbers more than once.

The simplest way for anyone to do it is simply to add the money paid- $160- versus the money made- $180. So no matter what the process in between you have to have made twenty dollars!

And now we can do yerss' one, though as he says, it is meant to be a quickfire (and, I believe, oral) question to quickly confuse a brain. I have more I can do when that one is done... the answer is 4100. I believe the trick is that if you rush through it you will say 5000.

Yep 4100 I get too, so it must be correct.

yea..4100..how can anyone possibly get 5000 out of that??