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An Odd Card Trick

chalkdustmagazine.com

31–40 of 46 posts

Re: An Odd Card Trick

#31
post #2

Just performed this trick for my partner and she was very underwhelmed. There’s probably a good delivery to figure out.

Yes - it boils down to “there are 10 cards. Pick some number of cards, give me the rest, and I’ll tell you how many you picked”. The addition of “more cards” very thinly disguises the basic fact that you are subtracting a number from 10. It’s not obvious to me how this could be done in a way that seems impressive.

Do the whole trick blindfold. And learn some patter.

Re: An Odd Card Trick

#32

The wine and water explanation doesn’t make sense to me. Wine and water have different molar masses and combining a liter of water and a liter of wine doesn’t give exactly two liters of the new substance, in the same way as a liter of ping pong balls and a liter of sand doesn’t produce two liters of ping pong sand when mixed together - some of the molecules are bigger than some of the others. Once you pour a liter of…

https://de.wikipedia.org/wiki/Mischungskreuz

Is there a name for this in English?

Re: An Odd Card Trick

#34
post #10

Earlier quoted context omitted.

TFA explains the trick somewhat oddly, to make the math angle more obvious. Here's a (random) video of someone doing it a more usual presentation of the effect: https://www.youtube.com/watch?v=Xau8Ng4aQ6Y Not the world's greatest magic trick or anything, but I don't think it's as transparently obvious to figure out as several commenters are suggesting.

The article describes a fixed number of cards to the performer and spectator, but the video has him split the deck behind his back. Is he counting by touch to have the correct number of cards?

Yes. That's what all the "but it's obvious!" commenters are missing - normally the spectator wouldn't have all the information that TFA lays out (that exactly half the deck starts out reversed, exactly how the cards are split up later, etc).

Re: An Odd Card Trick

#35
post #22

Earlier quoted context omitted.

No, it’s not like ping pong balls and sand. A liter of water and a liter of wine definitely make 2 liters of liquid…

Not quite. Mixing alcohol and water results in a different total volume than the sum of the two before mixing. https://en.wikipedia.org/wiki/Alcohol_by_volume#Volume_chang...

[deleted]

Re: An Odd Card Trick

#36

The wine and water explanation doesn’t make sense to me. Wine and water have different molar masses and combining a liter of water and a liter of wine doesn’t give exactly two liters of the new substance, in the same way as a liter of ping pong balls and a liter of sand doesn’t produce two liters of ping pong sand when mixed together - some of the molecules are bigger than some of the others. Once you pour a liter of…

Excluding the physical elements, it still seems a poor, possibly actively misleading (or should I say misdirecting), analogy.

The better way to understand it is to use only two cards, one face up one face down, if you give one to each person randomly, how can you magically match the other person? By flipping the card, because for every down you have, the other person has one up.

Re: An Odd Card Trick

#37

The wine and water explanation doesn’t make sense to me. Wine and water have different molar masses and combining a liter of water and a liter of wine doesn’t give exactly two liters of the new substance, in the same way as a liter of ping pong balls and a liter of sand doesn’t produce two liters of ping pong sand when mixed together - some of the molecules are bigger than some of the others. Once you pour a liter of…

You are being pedantic

Most people won't consider the sub ml change in volume

Re: An Odd Card Trick

#38
This reminds me of a self-working trick I saw online in the 90s.

The website shows you a hand of 5 cards, and asks you to pick one card and stare at it intensely. It claims it will read your mind and guess the card. When ready, you will click a button, and 5 new cards are shown - 4 random cards plus the card you thought of.

...

The trick is that the same cards are shown as before, but in different order. Most people only focused on the one card and don't notice that the rest of the cards are the same. It sounds very simple, but it worked on me and all my family members, at least the first time.

Re: An Odd Card Trick

#39

This reminds me of a self-working trick I saw online in the 90s. The website shows you a hand of 5 cards, and asks you to pick one card and stare at it intensely. It claims it will read your mind and guess the card. When ready, you will click a button, and 5 new cards are shown - 4 random cards plus the card you thought of. ... The trick is that the same cards are shown as before, but in different order. Most people…

Do you remember what site it was on? It sounds super familiar.

Re: An Odd Card Trick

#40

This reminds me of a self-working trick I saw online in the 90s. The website shows you a hand of 5 cards, and asks you to pick one card and stare at it intensely. It claims it will read your mind and guess the card. When ready, you will click a button, and 5 new cards are shown - 4 random cards plus the card you thought of. ... The trick is that the same cards are shown as before, but in different order. Most people…

I have seen the same concept where they show 5 cards, ask you to choose one and then click the button.

Then it shows the other 4 cards, with your card removed.

In reality of course it’s a similar set that contains none of the same cards.

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