# See if you can get this Maths Question right

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#### royaldank

##### Diamond Member
Originally posted by: mooncancook
hmm let me think again.

He gains \$3 total from the sale (21-18). Then he lose \$100 to the neighbor for the fake bill. 100-3=97.

So my final answer is \$97.

Exactly where does he gain this \$3? If the product never sold, sure. But, if I had walked in next and bought it (or if the guy had used a legit \$100), he would have made that \$3.

#### Glavinsolo

##### Platinum Member
Originally posted by: royaldank
This is like the bellhop riddle.

Three guys pay for a \$150 room with a \$50 bill each. Shopkeeper decides he overcharged \$5 and sends it up with the bellboy. He tells the guys and shows them the \$5. They decide to each take \$1 from the bellboy and let him have the extra \$2. So, each guy paid \$49 which equals \$147. Now, add the \$2 the bellboy has in his pocket and that's only \$149. Where's the extra dollar.

Easy

145/3 = 48.333

+1 = 49.333 (Each guy didnt pay \$49 they paid \$49.3333)

49.333*3=148

\$2 goes to bellboy

#### MobiusPizza

##### Platinum Member
Originally posted by: mobobuff
Originally posted by: royaldank
This is like the bellhop riddle.

Three guys pay for a \$150 room with a \$50 bill each. Shopkeeper decides he overcharged \$5 and sends it up with the bellboy. He tells the guys and shows them the \$5. They decide to each take \$1 from the bellboy and let him have the extra \$2. So, each guy paid \$49 which equals \$147. Now, add the \$2 the bellboy has in his pocket and that's only \$149. Where's the extra dollar.

That's easy actually
The price of room was overcharged \$5. The room cost for each person is (\$150-\$5)/3 = \$145/3 = \$48.333333

They paid \$49 * 3 = \$147 in total. Minus room cost \$145 = \$2 which the bellboy has.
The \$1 never existed

#### Barrak

##### Guest
He gave out 79 in change, 18 for the item, and another 100 to the other store for grand total of

197 net loss

#### mooncancook

##### Platinum Member
Originally posted by: royaldank
Originally posted by: mooncancook
hmm let me think again.

He gains \$3 total from the sale (21-18). Then he lose \$100 to the neighbor for the fake bill. 100-3=97.

So my final answer is \$97.

Exactly where does he gain this \$3? If the product never sold, sure. But, if I had walked in next and bought it (or if the guy had used a legit \$100), he would have made that \$3.

Remember he got \$100 from the neighbor in the first place? He gave \$79 in change to the buyer, so he keeps \$21 for the purchase. That \$21 didn't go back to the neighbor, it's his. So he makes \$3 out of it.

#### mchammer187

##### Diamond Member
Originally posted by: Barrak
He gave out 79 in change, 18 for the item, and another 100 to the other store for grand total of

197 net loss

if he gave out 79 in change why would he have to ask his neighbor for anything?

#### mobobuff

##### Lifer
Originally posted by: AnnihilatorX
Originally posted by: mobobuff
Originally posted by: royaldank
This is like the bellhop riddle.

Three guys pay for a \$150 room with a \$50 bill each. Shopkeeper decides he overcharged \$5 and sends it up with the bellboy. He tells the guys and shows them the \$5. They decide to each take \$1 from the bellboy and let him have the extra \$2. So, each guy paid \$49 which equals \$147. Now, add the \$2 the bellboy has in his pocket and that's only \$149. Where's the extra dollar.

That's easy actually
The price of room was overcharged \$5. The room cost for each person is (\$150-\$5)/3 = \$145/3 = \$48.333333

They paid \$49 * 3 = \$147 in total. Minus room cost \$145 = \$2 which the bellboy has.
The \$1 never existed

Just stop.

#### MobiusPizza

##### Platinum Member
Originally posted by: mobobuff
amoeba was actually the first to have the correct answer.

Sorry did I missed his post? Hm let me check...

Ah yes.
It would have been easier to notice if he gave a paragraph for an explanation.
At least to prove that it was not a mere guess

#### MobiusPizza

##### Platinum Member
Originally posted by: mooncancook
Originally posted by: royaldank
Originally posted by: mooncancook
hmm let me think again.

He gains \$3 total from the sale (21-18). Then he lose \$100 to the neighbor for the fake bill. 100-3=97.

So my final answer is \$97.

Exactly where does he gain this \$3? If the product never sold, sure. But, if I had walked in next and bought it (or if the guy had used a legit \$100), he would have made that \$3.

Remember he got \$100 from the neighbor in the first place? He gave \$79 in change to the buyer, so he keeps \$21 for the purchase. That \$21 didn't go back to the neighbor, it's his. So he makes \$3 out of it.

The neighbour did not gain nor lose anything

The neighbour gave the shopkeeper \$100 change while received a fake \$100 note. (-100)
The shopkeeper gave the neighbour \$100 afterwards for the worthless courtfeit note (+100)
That levels out to \$0 gain/lost for the neighbour

#### royaldank

##### Diamond Member
Originally posted by: mooncancook
Remember he got \$100 from the neighbor in the first place? He gave \$79 in change to the buyer, so he keeps \$21 for the purchase. That \$21 didn't go back to the neighbor, it's his. So he makes \$3 out of it.

If you still believe this, think of the problem this way.

I walk in with no money. I walk out with a \$21 product and \$79 in change. He's out \$100.

I walk in with \$100. I buy a \$21 product and get \$79 in change. He's made \$3 (price vs his cost).

If that item was never going to be sold to anyone, then \$97 would be correct. But, he missed out on his profit because he gave it away.

#### ABitTooSpicy

##### Senior member
I can't believe this thread is still going...

I'll throw my 2 cents in as well...

Come on people the answer is \$97 (Edit - uh i mean 115 hehe)

Lets say the shop keep started off with just one item that he paid 18 for:
Has item worth 18
(give and take happens)
Now he has 21 dollars
(he is up 3 at this point)
(Fake note happens and he has to hand over 100)

so 3 - 100 = -97... shop keep is down 97

edit - ok just realized he started off with 18 and is now at -97 so therefore he lost 18+97 = 115...

#### royaldank

##### Diamond Member
Originally posted by: ABitTooSpicy
I can't believe this thread is still going...

I'll throw my 2 cents in as well...

Come on people the answer is \$97

Lets say the shop keep started off with just one item that he paid 18 for:
Has item worth 18
(give and take happens)
Now he has 21 dollars
(he is up 3 at this point)
(Fake note happens and he has to hand over 100)

so 3 - 100 = -97... shop keep is down 97

edit - ok just realized he started off with 18 and is now at -97 so therefore he lost 18+97 = 115...

The item would have sold for \$21 if he had a legit \$100. He didn't. Shop keep didn't make this \$3. He would have been \$3 further ahead had he actually sold it instead of giving it away, which gives you the final answer of \$100.

#### ABitTooSpicy

##### Senior member
Originally posted by: royaldank
Originally posted by: ABitTooSpicy
I can't believe this thread is still going...

I'll throw my 2 cents in as well...

Come on people the answer is \$97

Lets say the shop keep started off with just one item that he paid 18 for:
Has item worth 18
(give and take happens)
Now he has 21 dollars
(he is up 3 at this point)
(Fake note happens and he has to hand over 100)

so 3 - 100 = -97... shop keep is down 97

edit - ok just realized he started off with 18 and is now at -97 so therefore he lost 18+97 = 115...

The item would have sold for \$21 if he had a legit \$100. He didn't. Shop keep didn't make this \$3. He would have been \$3 further ahead had he actually sold it instead of giving it away, which gives you the final answer of \$100.

You didn't read my edit =)

I changed answer from 97 to 115...

Edited again as I didn't like my \$3 explanation... lol

#### royaldank

##### Diamond Member
Ahh, yes. And the \$115 figure is much more accurate.

#### Amused

##### Elite Member
In reality, I would give my neighbor the finger, and keep the \$21. Thus making a net gain of \$3.

"OMGWTF??? That's not the bill I gave you!!!"

#### Yax

##### Platinum Member
He's out \$18 for the cost of the product.
He's out \$100 which he had to pay the neighbor.
Total loss: \$118.

#### chuckywang

##### Lifer
What's the answer? I'm convinced it's 97 dollars.

#### royaldank

##### Diamond Member
Originally posted by: chuckywang
What's the answer? I'm convinced it's 97 dollars.

\$100 as stated many times over.

#### Amused

##### Elite Member
Originally posted by: Yax
He's out \$18 for the cost of the product.
He's out \$100 which he had to pay the neighbor.
Total loss: \$118.

You're forgetting he kept \$21 out of the \$100 when he made change at the time of sale.

It's \$100 folks. Businesses count the lost profit as a loss when an time is stolen. They claim the retail price, not the wholesale price.

#### Yax

##### Platinum Member
Originally posted by: Amused
Originally posted by: Yax
He's out \$18 for the cost of the product.
He's out \$100 which he had to pay the neighbor.
Total loss: \$118.

You're forgetting he kept \$21 out of the \$100 when he made change at the time of sale.

It's \$100 folks. Businesses count the lost profit as a loss when an time is stolen. They claim the retail price, not the wholesale price.

NO, he didn't get to keep that because he had to give that to the other shop's owner. (\$100 payback). He lost \$18 which is the cost of the product so when you add that to the \$100, it makes \$118.

Edit: Well, what he claims and what he actually lost are different things. Ofcourse you're going to claim the lost profit. It makes good biz sense to do so.

#### r6ashih

##### Senior member
the shop keeper is out \$200

he gave 100 of product and change to the purchaser
had to repay 100 to neighbor

#### mchammer187

##### Diamond Member
Originally posted by: Yax
Originally posted by: Amused
Originally posted by: Yax
He's out \$18 for the cost of the product.
He's out \$100 which he had to pay the neighbor.
Total loss: \$118.

You're forgetting he kept \$21 out of the \$100 when he made change at the time of sale.

It's \$100 folks. Businesses count the lost profit as a loss when an time is stolen. They claim the retail price, not the wholesale price.

NO, he didn't get to keep that because he had to give that to the other shop's owner. (\$100 payback). He lost \$18 which is the cost of the product so when you add that to the \$100, it makes \$118.

you are saying the shop owner is getting a free \$21 out of the deal

neighbor gives change \$79 to the customer but makes the first owner pay him back \$100?

#### MobiusPizza

##### Platinum Member
The answer is \$100 as stated at page 5

Basically what Amused said
Its not \$97 as if the buyer didnt cheat the shopkeeper would have earned \$3 by selling the \$21 product
-\$100 would be what the shopkeeper would put down in his account book

#### piasabird

##### Lifer
First he lost \$100.00 to his friendly neighbor shop keeper, Then he lost \$71.00 that he gave the Customer in change. Then He lost the cost of the Item which was \$18.00 and the profit which was \$4.00. He also should have collected Taxes on the item he sold, But he may not have to pay that since Forgery may have been involved.

This is somewhat complicated because you may or may not count the \$4.00 in Profit, but I think you have to because that is the lost opportunity cost. You could also add in an approximation of what it took to order the item and have it delivered, and what the space on the shelf represents as a part of the fixed cost to maintain the store and store the item and pay your employees, electricity, etc.

Oops \$3.00 in profit.