What is the Cost of a book that costs 1$ plus half of its price?

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The discussion revolves around a mathematical riddle regarding the cost of a book priced at $1 plus half of its price. Various interpretations of the question lead to different conclusions about the book's cost. Some participants argue that the book costs $2, derived from the equation x = 1 + 0.5x, while others suggest it could be $1.50 or even $0.50, depending on how the question is understood. The conversation highlights confusion over the terms "cost" and "price," with some participants suggesting that the wording of the question could lead to multiple interpretations. Ultimately, the majority consensus leans toward the book costing $2 based on the mathematical formulation, although playful banter about the nature of the question persists.
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I don't know if this already been posted but here it goes:


What is the Cost of a book that costs 1$ plus half of its price?
 
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1/2x + 1 = x

x=2

The book costs $2?
 
Oriako said:
1/2x + 1 = x

x=2

The book costs $2?

Nope.
 
The book is priceless. :D
 
Book has a price, and i don't think anyone here can find it.
 
Deicider said:
Nope.

I don't understand why you think Oriako is wrong, please explain.

DaveE
 
>What is the Cost of a book that costs 1$ plus half of its price?

The answer is $1.50.

As you stated, the book costs $1.00.
Add half its price and the cost becomes $1.50.
 
Goongyae said:
As you stated, the book costs $1.00.
Add half its price and the cost becomes $1.50.

Ok, so the fault is with English, then? The difference between:

What is the Cost of (a book that costs 1$) plus (half of its price)?

Versus:

What is the Cost of a book that (costs 1$ plus half of its price)?

DaveE
 
So the book either costs 1$, 1.5$, 2$ or infinity$...

I have a feeling the thread will turn out to be like: http://www.xkcd.com/169/
 
  • #10
LMAO @ this thread

I still want to know if my answer of $1.50 was correct or not.
 
  • #11
Are you going to tell us the answer? I'm intrigued what it could be...
 
  • #12
Not this nonsense, again. You've posted this in another forum, trying to play poorly-worded games with "price" versus "cost".

Ignoring the silly nonsense, with "cost" and "price" being synonyms, the answer is of course $2.
Pay attention to the silly nonsense and the answer is a cumquat (or whatever you want).
 
  • #13
D H said:
Not this nonsense, again. You've posted this in another forum, trying to play poorly-worded games with "price" versus "cost".

Ignoring the silly nonsense, with "cost" and "price" being synonyms, the answer is of course $2.
Pay attention to the silly nonsense and the answer is a cumquat (or whatever you want).

Nope.
Still wrong answer.
 
  • #14
If P = price and C = cost, then C = $1 + P/2. For instance, for a dime novel, the price is $0.1 and the cost is $1.05. That's why you don't see dime novels anymore. However, for a book with a price of $1,000,000,000,000,000,000,000,000.02, the cost would be $500,000,000,000,000,000,000,001.01 and since this is beyond the means of most publishers, you don't see these kinds of books anymore either.
 
  • #15
I've finally solved it! The answer is either $0.50 or $0.98.

>What is the Cost of a book that costs 1$ plus half of its price?

We have the profit of buying the book at -$1, plus half the price of the book at $0.50, for a total profit of $-0.50, or a total cost of $0.50.

But what if the statement means "What is the Cost of a book that costs one dollar, plus half of its (the dollar's) price?"

It is impossible to buy a dollar anywhere (you can certainly trade something for a dollar, but it's not called "buying" a dollar). Therefore the only meaningful price atributable to a dollar would be the price paid by the Treasury Department to manufacture it, i.e. $0.04.

Thus we have the profit of buying the book at -$1, plus half the price of the dollar at $0.02, for a total profit of $-0.98, or a total cost of $0.98.
 
  • #16
Goongyae said:
I've finally solved it! The answer is either $0.50 or $0.98.

>What is the Cost of a book that costs 1$ plus half of its price?

We have the profit of buying the book at -$1, plus half the price of the book at $0.50, for a total profit of $-0.50, or a total cost of $0.50.

But what if the statement means "What is the Cost of a book that costs one dollar, plus half of its (the dollar's) price?"

It is impossible to buy a dollar anywhere (you can certainly trade something for a dollar, but it's not called "buying" a dollar). Therefore the only meaningful price atributable to a dollar would be the price paid by the Treasury Department to manufacture it, i.e. $0.04.

Thus we have the profit of buying the book at -$1, plus half the price of the dollar at $0.02, for a total profit of $-0.98, or a total cost of $0.98.

Not correct but you're close.
Go for it, i see the potential in you.
 
  • #17
Deicider said:
I don't know if this already been posted but here it goes:What is the Cost of a book that costs 1$ plus half of its price?

Well...lets see...

Case 1: as the question is worded, the book costs $2

Case 2: we take the question at face value and don't think about it too much, the book costs $1

Case 3: the book costs 1 dollar and is then marked up by 50%, the book costs $1.50

Case 4: because Cost is capitalized, it is obviously referring to the manufacturer's cost of making the book. Assuming that the manufacturer sells it at a 10% profit, the store then sells it again for a 10% profit, and we use the value from case 1, the book Costs about $1.65

Case 5: see goongyae's https://www.physicsforums.com/showpost.php?p=3171447&postcount=15", i like it (but if you combine both parts, wouldn't the book end up costing either $0.52 or $1.52, depending on interpretation of the word "plus"?)

Case 6: we hire the professional detective from this https://www.physicsforums.com/showthread.php?t=477512", who then promptly investigates the matter and informs us that our initial value of $2 is correct
 
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  • #18
the Cost of a book that costs 1$ = 1$
 
  • #19
is it either 2.25 or 3.375 ? or something along those lines...like the number plus half of itself repeatedly? or it is either an infinite amount of $'s.or is it free?
 
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  • #20
f(x)'s first case is correct.

Cost of the book is x. The question reads as cost of the book equals $1 plus half the cost of the book.

So: x=1+.5x


Thus: x=2
 
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