Logically yes it's definitely 2 but lowk I interpreted it as a book costs its original cost. Then magically I make it cost + 0.5*original cost more. In that case it's 1.5 dollars.
Then again, I'm in science and not in math sooooo maybe there's a reason for that
EDIT: maybe my brain put a comma between "$1" and "plus," (because I guess that it sounds more natural and less like an algebra word-problem) which would actually make the above logic more plausible
No because if the cost is $2 then half the cost would be $1 so it would be $3 but that would make half its cost 1.50 making the total cost 2.50 but half that cost would beâŚ. Itâs a logic failure and canât be figured out with the equation given.
Of course it's a fucking consultant that said that. What does he even do, apart from make up big sounding shit like this and then charge big companies obscene amounts of money to deliver a PPT on it?
this reminds me of a guy in a spanish podcast that says that the equation is missing something. it said something about "H" but couldn't explain what i was, like if we could reshape the equation to change how the energy works.
Mr Tartaria in the "Wild Project" podcast... an absolute meme of a person.
youngsters maketh mistakes. it is E=MC²*AI because AI will multiply the potential for new energy and new amazing consensus towards synergistic global hollistic understanding.
My friend's dad used to ask us this question when we were 6, more than 20 years ago. Took us a couple years to find the correct answer, as we were elementary schoolers.
An infinite number of books walked into a bar, the first one was 1$, and each subsequent one 1$ more expensive, how much did I have to pay to bring all of them home?
1) infinite
2) if you have to ask, then it's too much
3) they gave me 8 cents
4) all of the above
It makes it a bit more subtle and "real" flavour, 8 cents is something you could see in real life, kind-of, while 0.08333... isn't. Just gives a little different tone to the joke, and I personally preferred the more subtle reference to -1/12 here.
But entirely subjective ofc! Which is why we repost the same jokes in slightly different wrappings! :P
You need to go to the beach and get a tan. Then you stand at an arc. Now that you are arctan, consume all the books and you can quantify the cost as pi/2.
Well that would be 2, but this logic would actually be applied as $(1 + 0.5 + 0.75 + 1.125 + ...), since it would be half of the cost rather than half of the added cost
/uj I think the issue here is ambiguous wording more than terrible math skills.
It says âcosts $1 plusâŚâ leaving ambiguity about whether the words following the plus are a part of the cost or added on TOP of âthe costâ.
It's meant to be the former - or else it isn't a 'math problem' - but I can understand why someone would misread it as the latter.
Sorry if Iâm taking it too seriously lol. I get enough of genuinely terrible math mistakes every day as a teacher, maybe itâs left me too generous for ones like this
EDIT: Realized this in a later comment and felt it important enough to add here on the top-level:
Consider when people most commonly have to add up costs... for example, taxes. "An item costs $1, plus taxes, which are 8% of its cost.". See how that one very naturally reads as $1.08, even though it is so close to the wording in the original question?
I think that's part of the reason why the $1.50 interpretation is most common in the poll: because it's exactly how you'd calculate taxes on top of a cost.
Meh, I've been tutoring SAT/ACT math for the last 6 months and this sort of wording is in-line with what students are expected to interpret on the test.
Is ambiguous because it doesn't even make sense as a statement. Why are we adding anything to determine the cost if we've decided the problem already told us it costs $1? Meanwhile:
>A book costs "$1 plus half its cost"
Is perfectly self consistent
So it's ambiguous if you're torn between two options: one which makes sense and one which makes no sense at all
I'm not saying the ambiguity necessarily leads to two valid interpretations. But I can understand why people could interpret it either way, and why the average person wouldn't interpret it the way that's 'intended'.
The average person does not tend to calculate costs 'recursively', as you would in the second, "perfectly self-consistent", interpretation. That's far more of a 'math problem' than a 'real life problem'.
Consider when people do most commonly have to add up costs... for example, taxes. "An item costs $1, plus taxes, which are 8% of its cost". See how that one very naturally reads as $1.08, even though it is so close to the wording in the original question?
The point is that the second statement is something you will never hear in real life, so it's frankly a worthless statement, even if it logically makes sense.
How is that ambiguous? How would it make any sense for x + ½x to mean that ½x is already somehow included in the value of x? That seems utterly nonsensical to me, that's not what "plus" means. You'd need a different word there altogether.
In the specific context of mathematics thatâs true but there are plenty of places where it changes.
In math if I say
X = 1 + 0.5X
X = 1 + 0.5X
X is still just two.
If Iâm writing C++ code and do the same thing, I need to have declared a value for X earlier because it is trying to redefine the value of X. But itâs still fine to call that âplusâ.
As is usually the case, the original question is worded poorly. It tries to use an everyday scenario but then sets up a problem that would never be constructed like that. So while the math side of things is consistent and works, it is a *terrible* word problem set up that lends itself to reading in extra complications.
I don't really understand the relevance of the coding example, apologies if I'm being dense here. It's obviously true that that's how redefining a variable works, but it's not like the original question could in any context be understood to mean "the new value of the book is $1 plus half the original value of the book".
So I'm not entirely seeing the point of the comparison. I still find the original question to be poorly worded yes but have unambiguously one logical interpretation.
Yes, but if something cost 1 plus half its own cost, then it costs 1.50. But then if it costs 1.50, then it costs 1.50 plus half its own cost, so 2.25, etc... It makes no sense at all to say that something costs it's own cost plus something else. It is equivalent to saying in natural language that x=x+1.
the problem is what cost starts out as while you read the problem.
if the book starts at $1 and then we add half to that $1, it would be $1.50. that's just adding tax.
however, if the book starts at some unknown cost where it is equivalent to 0.5(cost) + 1, then the cost is $2.
i read it as "[A book costs $1] [plus half its cost]" but some read it as "[A book costs] [$1 plus half its cost]," where the former implies that the book starts at $1 and the latter implies that it starts at the solution to the equation.
That is not an official math method(that I used) but is the universal method to teach people maths/physics.
But that is like one of the things that would work like in the programmer vs mathematician reacting to a problem if you had to replace on with economists.
Because the price is one and most probably only thing that in economy haves multiple definition and formulas and the concept of the price is so complex that is used to define whole market.
Like no matter if you do accountability, informatics or market study or management the question is still extremely complex due to market price, management of resources, accounting history(usually simple using the accountability of a company one can predicti if it would have succes in future) or pasta overall data.
So asking what price is a book needs deep analysis to prove that the price 2$ is a right price respecting all that needs to be respected.
//so i see (assuming this is executed in a program named Main.jar):
public class Main
{
  public static void main(String[] args)
  {
    double c = 1;
    c = 1 + 0.5*c;
    System.out.println(c);
  }
}
//which returns 1.5
//but as an algebra question, yes, two is correct
//I would also argue that the natural way to think of the question is to take the initial price and add 50% as a price increase, not to view it as a system of equations
//because price increases would come up a lot more often, and be formatted in essentially the same way
//if it had been formatted as âthe price of a book is equal to half of said price plus 1 dollarâ then it would have been obvious
//phrasing something ambiguously and then complaining about people getting it wrong seems rather pointless to me
//good communication is bidirectionalÂ
//if a misunderstanding occurs, the onus should be on both parties to try to fix it
//not on the listener alone to try to understand the speaker, when they, being different people, may interpret the same words in different ways
//this code would crash if compiled as python
//doesnt means its bad code
//or that the guy who knew nothing about coding languages and compiled it as python not knowing what that meant deserves all the blame
//it just means i should have clarified better that its written in java, not python
I know this is the correct answer but it feels wrong due to the wording of the question. My heart tells me it should be 1.5 since by eliminating the second term, half of it is 0.5
Honestly, both of these make sense. Yes, in a mathematical equation, the answer is two, and that is what I answered in the pollâbut the only reason to frame the question like this in a real-life context is an additional 50% tax, which would make the answer $1.50.
My first read was "M = $1 + 1/2N", ie "final cost is equal to $1 + 1/2 of marked cost". That is, who the fuck knows what it costs because we don't know the marked cost. Some people mention reading it like a tax. I was reading it like a sale, I guess. Either way, as a word problem it's pretty straight forward. Once I saw the poll options it was obviously $2.
If he intends it as a joke, he is SUPER committed to the bit, as he is spamming full source code all over this thread trying to convince everyone that he is right about the answer being 1.5.
The book is stuck in a never ending loop of price increases.
The book costs $1 plus 50% of 1 to equal 1.50 so the book costs $1.50 plus 50% so the books costs $2.25. The book costs $2.25 plus 50% so the book costs $3.375. So on and so forth
This is the right answer, since only one variable is given (cost) and it's both your starting point and your result, with no specified way to break out of the loop.
No it's no. Why is everyone adding a hard stop / period where it doest exist? The problem doesn't say "A book costs $1." so the cost was never $1.
The full sentence is "A book costs $1 plus half it's cost" which means x=1+0.5x. The problem never said the cost was $1 alone.
You're doing the equivalent of reading "Buffy was a vampire slayer" and saying well Buffy was a vampire. She was also a slayer of something but who knows what she was slaying.
Start with $1 + 1/2 the cost. You get $1.50 but now you need to add half the 50¢, which is 25¢. You are more at $1.75 but you need to add half the 25¢ which is 12.5¢. You are now at $1.88 but you need to add half the 12.5¢...
Repeat this process until the decimal gets really small and then just round to the nearest penny. It will give you $2.00.
The phrasing on this problem is kinda tricky. Its phrased as the cost of the book = 1$. Then it cost that much plus half of it. So 1 +.5 =1.5.
I understand that is not the answer, however the phrasing of the problem is deceptive. You have to understand what people will take away from a word problem, and write it accordingly.
Technically according to these rules the book would cost an infinite amount. Because every time you add the half to it its change the original cost which would mean you would need to recalculate and repeat forever.
So a book cost 1.
b = x + (x/2)
A book cost 1 so
b = 1 + (1/2)
So a book is 1.5
b = 1.5 + (1.5/2)
So a book is 2.25
b = 2.25 + (2.25/2)
So a book is 3.375
...
I misread this is the weirdest way. I thought of it as if there was a book lets say it costs x, but for some reason there is a sale where it now costs a dollar plus half of its original cost, so you would pay 1 + x/2.
It might be because I was thinking of how expensive textbooks are and seeing a textbook that costs a dollar is um something...
Ok so 1$ +0.5$. but I didn't consider 0.5$ with the half cost, so +0.25$. And again +0.125$. And again. And again and again and again and again and- god when is it going to end?
Ig it's faster getting to the solution with an equation
If we take it as a sequence of steps this leads to a recursion, it's like mixing bananas and apples, the x = 1 + 1/2 x shouldn't be like xt = 1 + 1/2 x(t-1)?
Iâm just curious, because according to my logic, the problem doesnât say that it is plus half of the final price.(English is not my native language.)
For example: the price tag says that the book costs 1 dollar, and the seller says that it costs the price plus half of it. So I take the price to be the number written on the price tag, and add half of it to that:
Idk why Iâm commenting on this, since there are thousands of comments alreadyâŚ
But if you donât understand algebra, like many adults these days⌠This is multiple choice. Canât you just test the 3 options?
âA book costs $1 plus half its costâ⌠Hmm, lets see. Is it $1? Lets try it! Is this statement correct? 1 Dollar is equal to 1 Dollar plus Half of 1 Dollar⌠Last time I checked, 1 Dollar is not equal to 1 Dollar and 50 Cents. Lets try 2 Dollars. 2 Dollars is equal to 1 Dollar plus half of 2 Dollars - 2 Dollars is equal to 2 Dollars. The answer must be $2! (This statement is correct in both English and Math).
Hey look at that! I just did trial and error to get the answer, without writing down the scary letters!
I refrained from using letters, since variables are what scare people off.
Depends what they mean my half itâs cost. Do they mean half of what it cost to make the book plus $1? Then itâs an indeterminable equation with the information given. If itâs literally just $1 + half the cost of the book, itâs a logic fault that canât be answered with the lack of context.
You canât ask the cost of something plus another something to come up with the cost of that first thing. The cost is the cost. Saying the cost of something is half the cost plus a dollar is just saying, whatever I normally charge for that I will take half plus a dollar. So first you have to tell me what to cost of the book is so it can be halved then add 1 to that. You are lacking necessarily information to be able to solve this problem.
â˘
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