iq 130+ simple but confusing brain teaser.


by gooksahn
Tags: brain, confusing, simple, teaser
gooksahn
gooksahn is offline
#1
Oct11-07, 04:54 AM
P: 1
you are a jewelry shop owner.

one day a customer comes in to buy a $70 ring. He only has a voucher worth $100. you do not have any cash around, so you go next door to the pastry shop and ask the owner to change the $100 voucher for cash. the pastry shop owner gives you the cash.

you go back to your shop and give the customer $30 in change along with the ring.

10 minutes later, the pastry shop owner comes in angry and tells you that the voucher is fake, and that he wants his $100 back. you apologize and give him the $100.

question: What is your total loss? (the ring indeed is $70)


many have answered this wrong. please think it through.
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J77
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#2
Oct11-07, 05:09 AM
P: 1,157
$130 ?
Valayar
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#3
Oct11-07, 05:16 AM
P: 4
I'd say 100 $.

Here is my explanation :

Suppose the ring is exactly 100 $. Going to plastry shop to exchange the voucher would be useless (has he wouldn't have to give any cash back), but let's do it : he exchanges the voucher for cash, and afterwards the plastry shop owner comes back and takes his money back. Then the jeweler would have lost the price of the ring, which is 70 $.

However the ring isn't 100 $, it's 70 $. So the jeweler gives back 30 $ in cash.

Finally, he has lost 70 + 30 = 100 $.

J77
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#4
Oct11-07, 05:49 AM
P: 1,157

iq 130+ simple but confusing brain teaser.


I should stick in an explanation -- you lose $70 on the ring, $30 to the customer and $30 to the baker...

or am I missing something as I chomp on my lunch...?
Jimmy Snyder
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#5
Oct11-07, 06:39 AM
P: 2,163
Answer:

The jeweler lost $100, the customer gained $100, and the baker neither gained nor lost.

Assuming the voucher to be a worthless piece of paper, I won't mention it any longer
The customer received a $70 ring and $30 cash and gave nothing in return for it. He made $100.
The baker gave the jeweler $100 and the jeweler gave the baker $100. Neither the jeweler nor the baker gained nor lost on this transaction.
The jeweler gave the customer a $70 ring and $30 cash and got nothing in return for it. He lost $100.

eom
belliott4488
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#6
Oct11-07, 07:23 PM
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I don't get this (and haven't yet looked at jimmysnyder's anwer). If you had no cash at the start, received $100 cash from the baker, then gave $30 to the customer, how did you have $100 to return to the baker? It seems you'd have only $70 cash left.
In any case, if we are to assume that somehow you gave the baker $100 back, let's say you wrote him a check, then it sure seems to me that you're out that $100, but that seems like the "obvious" answer to me, so I assume it's wrong.
Am I missing something?
akhil982
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#7
Oct14-07, 11:49 PM
P: 6
You lose 100 $....imagine u lost the voucher(same as fake.) All u did is u borrowed 100$ from neighbour and repaid 100 $ to him again. All u lost was ur ring (70$) and additional 30 $. That makes a total loss of 100$
momogiri
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#8
Oct15-07, 01:24 AM
P: 52
:/ I thought since the Jeweller gave away $100 to the neighbour, plus $70 ring and $30 change to the guy, wouldn't it be $200 all-together? XD
Sleek
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#9
Oct15-07, 05:48 AM
P: 59
$100 indeed. The owner makes a loss of $70 from the ring. The $100 he received is now only $70 (because he gave $30 to the purchaser). He thus has to throw in $30 from his own pocket.

Or a much more simpler way of looking at this is, The customer did not pay the shopkeeper anything (since the coupon was fake). But the Shopkeeper paid the customer (effectively) $70 ring +$30 = $100.
belliott4488
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#10
Oct15-07, 06:35 AM
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Quote Quote by momogiri View Post
:/ I thought since the Jeweller gave away $100 to the neighbour, plus $70 ring and $30 change to the guy, wouldn't it be $200 all-together? XD
No, the $100 he gives to the neighbor is just the same $100 that the neighbor gave him, so his net loss is $100.

The OP said many people get this wrong - is this the mistake they usually make?
daveb
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#11
Oct15-07, 09:59 AM
P: 927
Even though the problem says the jeweler doesn't have any cash around but then pays the baker back, i'll ignore that little error. If the jeweler starts with "x" dollars, gets +100 from the baker (for the voucher), and gives the ring and -30 to the buyer, he is left with 70 dollars and no ring. Then when the baker comes back, he pays 100 dollars so is 30 dolalrs in the hole along with the ring.
moe darklight
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#12
Oct15-07, 12:53 PM
P: 411
my answer is $200 due to the wording of the question.— it doesn't matter if the neighbor gave him that money in the first place; the question is "what is his total loss." even if he's giving the $100 to the same person who gave it to him, it was given to him, not lent, therefore he lost it.

had the question been "what was his net loss from the transaction," I would've said $100.
Kittel Knight
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#13
Oct16-07, 07:15 PM
P: 106
He has accepted a bad voucher. So he lost the $100. Thats all.
Evo
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#14
Oct16-07, 07:19 PM
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Has no one considered the fact that as a business the ring would not have cost him $70, unless he's crazy, the $70 price would have included a profit. So his "real" loss is unknown, since he might have never been able to sell that ring for $70 to a legitimate customer.
Kittel Knight
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#15
Oct16-07, 07:28 PM
P: 106
Quote Quote by Evo View Post
Has no one considered the fact that as a business the ring would not have cost him $70
Read again:

Quote Quote by gooksahn View Post
...
question: What is your total loss? (the ring indeed is $70)
Evo
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#16
Oct16-07, 07:35 PM
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Quote Quote by Kittel Knight View Post
Read again:
If the ring only cost the jeweler $20, his "real" loss on the ring was only $20, not $70.
Kittel Knight
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#17
Oct16-07, 07:45 PM
P: 106
Yes, but in this case what would be the meaning of saying twice(!) the ring is $70?
Evo
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#18
Oct16-07, 08:00 PM
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Quote Quote by Kittel Knight View Post
Yes, but in this case what would be the meaning of saying twice(!) the ring is $70?
Nothing.

I'm just getting nitpicky with the wording. The correct question would be what would be the anticipated, or projected loss. The real, or actual loss is unknown since we weren't told how much the ring cost the jeweler.


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