Iq 130+ simple but confusing brain teaser.

In summary: I...but... :uhh:Ok, so you're saying that the voucher was worthless and that the baker got ripped off for $100. How do you figure that? The baker gives the jeweler $100 and gets $100 back. The jeweler gets a $100 voucher from the customer and gives that $100 voucher to the baker. The customer gets a $100 ring and $30 in cash, which the jeweler gets back. The jeweler gets $100 from the baker and $30 from the customer, the customer gets $100 in goods, and the baker gets a $100 voucher and $30 in cash. How does anyone get ripped off in this transaction? The jeweler
  • #1
gooksahn
1
0
you are a jewelry shop owner.

one day a customer comes into 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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  • #2
$130 ?
 
  • #3
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 $.
 
  • #4
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...? :biggrin:
 
  • #5
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
 
  • #6
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?
 
  • #7
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 $. That makes a total loss of 100$
 
  • #8
:/ 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
 
  • #9
$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.
 
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  • #10
momogiri said:
:/ 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?
 
  • #11
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.
 
  • #12
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.
 
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  • #13
He has accepted a bad voucher. So he lost the $100. Thats all.
 
  • #14
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. :tongue2:
 
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  • #15
Evo said:
Has no one considered the fact that as a business the ring would not have cost him $70

Read again:

gooksahn said:
...
question: What is your total loss? (the ring indeed is $70)
 
  • #16
Kittel Knight said:
Read again:
If the ring only cost the jeweler $20, his "real" loss on the ring was only $20, not $70.
 
  • #17
Yes, but in this case what would be the meaning of saying twice(!) the ring is $70?
 
  • #18
Kittel Knight said:
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. :wink:
 
  • #19
Kittel Knight said:
He has accepted a bad voucher. So he lost the $100. Thats all.

nope. I stand by my word. he traded the voucher for $100 (made $100; it does not matter that the voucher is not actually worth the $100; he did make a $100 transaction), then he had to give back the $100 (that's him losing $100 and gaining nothing). then the $100 from the rest of the deal (the 70 + 30) = $200 gross loss and $100 net loss.

the wording of the question implies gross loss.

evo is also right, unless he's a terrible businessman, he would not have payed $70 for something he'll be selling at $70... and what about taxes? percentage of his earnings going towards employees, insurance? ... I dunno, this question is hard to answer without being given all the necessary info. I demand tax return print-outs and receipts!
 
  • #20
When I get into work I'm going to get some friends together and act this out -- just to settle it once and for all... :wink:
 
  • #21
I agree with belliot

if he didn't have $30 to make change for the 100, then he couldn't pay back the baker. He only has $70 cash.

But assuming he borrowed another $30 or wrote a check, then his loss is certainly $100 and kittle knight has the simplest explanation.
 
  • #22
loss= $70 ring + $100 paid to his neighbor
gain= $70 in change from his neighbor

net= $100
 
  • #23
moe darklight said:
then he had to give back the $100 (that's him losing $100 and gaining nothing).

The jeweler only lost $30 here, because from the $100 he borrowed from the baker, he had $70 of this still left over from the transaction with the customer because he had to give $30 of it away as change. So he only had to dig up 30 extra dollars to repay the baker.

So the jeweler lost the ring + $30.
 
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  • #24
$100

Jeweler makes no money from the sale of these types of rings (I guess its a hobby for him or something).

Given the fact that he only breaks even on sales of this particular ring, he had to shell out $100 to the baker.

Basically the customer made $100 (ring plus $30 change) and the baker got back his loss of $100 which caused him to break even. So where did the $100 come from? The poor jeweler.

Hope that makes sense.
 
  • #25
moe darklight said:
$200 gross loss and $100 net loss.

the wording of the question implies gross loss.

you can't convince me! muahahaha :devil:
 
  • #26
The question cannot be answered because we are not given how much of a profit does the jeweler make in selling the $70 ring properly. Losing the ring does not amount to losing 70$, it indeed amounts to losing less than that. And selling the ring doesn't amount to gaining $70, it amounts to gaining lesser as well. The jeweler lost (value of the ring) + $30.

Edit: I see Couperin got it right.
 
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  • #27
$200
 
  • #28
There is some confusion displayed here with the concept of the "sunk cost"

The two transactions with the pastry shop owner net out.

The jeweler gave $30 and a ring he could have sold for $70 to the man in exchange for nothing.

It doesn't matter what the jeweler paid for the ring,or any concomitant profit, because what he paid doesn't change whether he sells the ring or gives it away. The marginal transaction is the forgone $70.

Therefore, he has foregone $100
 
  • #29
regor60 said:
There is some confusion displayed here with the concept of the "sunk cost"

The two transactions with the pastry shop owner net out.

The jeweler gave $30 and a ring he could have sold for $70 to the man in exchange for nothing.

It doesn't matter what the jeweler paid for the ring,or any concomitant profit, because what he paid doesn't change whether he sells the ring or gives it away. The marginal transaction is the forgone $70.

Therefore, he has foregone $100

The loss from his prior to losing the ring fortune is $30 + value of the ring. The loss from potentially selling the ring is $100. The problem is really straight forward if we ignore the $30 - a simple theft of the ring. Having the ring stolen from you makes you (value of the ring) poorer. But had you sold it, you would have been $70 richer than you are now. The $30 just adds to the agony. ;)
 
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  • #30
Werg22 said:
The loss from his prior to losing the ring fortune is $30 + value of the ring. The loss from potentially selling the ring is $100. The problem is really straight forward if we ignore the $30 - a simple theft of the ring. Having the ring stolen from you makes you (value of the ring) poorer. But had you sold it, you would have been $70 richer than you are now. The $30 just adds to the agony. ;)

No need to quote me unless you're disagreeing, but it's hard to tell from your post. No point in ignoring the $30 since that's what was "given" away in addition to the ring, leading to the $100 marginal loss. The simplest way to look at it is...gave away the ring, gave away $30
 
  • #31
You don't get it. The loss, at least the loss the question is asking for, is $30 + value of the ring. The loss you are talking about is the potential loss.
 
  • #32
Once the government finds out about this, they are going to make up the jewelers loss out of my pocket. They will increase my taxes by $150, take $50 for administrative costs, give $50 to some rich guy who has nothing to do with this problem (unless they happen to be the ring thief) and the other $50 to the jeweler. See if this isn't how they solve the subprime crisis.
 
  • #33
Evo said:
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. :tongue2:

Yeah, I was wondering if we're talking about cash or value.
 
  • #34
Started with 0. Got 70 bucks. Lost 100. Ended up with 30 bucks lost. (and I would consider the ring lost as well as he gained pretty much nothing from it)

In my opinion the 100 dollars fooled with everyone. That was never the jewelers money, thus he never had it until he sold the ring for 70 dollars. I am probably wrong, but this is how I see it.

x = 0+70-100. x = $-30
 
  • #35
130 imo

the customer walks in
you give him the ring, you lose $70
you go to the baker, get $100
give the customer $30, you lose $100 total
you have $70 cash left from the $100 the baker gave you
you give the $70 + an extra $30 back to the baker
you lose $130
 
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