So I have a problem...

You have four small chains with three links each. You want to combine the four small chains into one necklace you can wear around your neck. It costs you ten cents to break a link of chain, and 20 cents to weld it together. What is the least expensive price you can pay to create a necklace of 12 links around?

Someone can explain it to me? Thanks.

Note by Half Pass3
3 weeks, 6 days ago

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90 cents I think. You can take one of the chains, break all its 3 links, then use them to join the rest into one necklace. This gives us 3 breaks and 3 welds, which amounts to 90 cents.

@Half pass3

Percy Jackson - 3 weeks, 6 days ago

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I have to state, 10 cents to break a LINK instead of a whole chain. and to make all 12 pieces into a circle.

Half pass3 - 3 weeks, 3 days ago

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So is my answer correct @Half pass3?

Percy Jackson - 3 weeks, 3 days ago

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@Percy Jackson Not a same problem but See Here. That last line there should've been here.

Devbrat Dandotiya - 3 weeks, 3 days ago

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@Devbrat Dandotiya See the solution is same as mine.

Percy Jackson - 3 weeks, 3 days ago

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@Percy Jackson @Percy Jackson, your answer was right.

Half pass3 - 3 weeks, 3 days ago

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@Percy Jackson @Devbrat Dandotiya sorry to tell you, but I checked and @Percy Jackson 's answer was correct.

Half pass3 - 3 weeks, 3 days ago

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If by links you mean the rings themselves, then there are 12 rings in total already, hence you can only weld, which will be four times for four chains, or 20×4=80 cents.

If by links you mean the connections between the rings, then there are 16 rings in total. Here three chains would be enough to make a 12 rings necklace and 3 welds are the only requirement, or 2×30=60 cents.

Devbrat Dandotiya - 3 weeks, 6 days ago

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Don't forget that you have to break a link before welding it to join two chains, so both your answers are wrong @Devbrat Dandotiya

Percy Jackson - 3 weeks, 5 days ago

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Don't forget that that is already the reason why welding is more expensive

Devbrat Dandotiya - 3 weeks, 5 days ago

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@Devbrat Dandotiya Thanks for helping me out so much.

Half pass3 - 3 weeks, 5 days ago

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@Devbrat Dandotiya Nope, that hasn't been mentioned. Practically even, breaking a link is much is easier than welding it, so welding is costlier. If it is so, then @Half pass3 hasn't stated his problem very well, and has left the solvers to guess out the specifics. If that is not the case, then I am simply correct, and you aren't @Devbrat Dandotiya :)

Percy Jackson - 3 weeks, 3 days ago

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@Percy Jackson Even if the problem isn't stated very well @Percy Jackson my solution makes less assumptions than yours.

Devbrat Dandotiya - 3 weeks, 3 days ago

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@Devbrat Dandotiya Actually, your solution makes the impractical assumptions that would simplify this problem. I took the practical assumption in my problem. You might as well have said that you could do it in 0 cents because a magic fairy helped you. In chain links, you always break and then weld, and welding usually costs more as it requires more work and precision than breaking a link.

Percy Jackson - 3 weeks, 3 days ago

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@Percy Jackson If I want to 'simplify' this problem which has already no specifications then I'm just being rational and hence it's not just about making 'impractical' or 'practical' assumptions but about making none or some.

Devbrat Dandotiya - 3 weeks, 3 days ago

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@Devbrat Dandotiya You are not making sense, as you are stating the same argument using different words again and again. Silence is the best answer to those who don't value your words, so I'm putting a pin on this conversation, and ending it. No use explaining it to people who don't accept they are wrong...........

Percy Jackson - 3 weeks, 3 days ago

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@Percy Jackson I might have agreed with you on the fact that the problem is poorly stated, but my reason of argument is that you've in the first reply claimed that my answers are wrong, as if you know what the question really should have been. If only by bringing the argument of 'assumptions' again and again I've become nonsensical, then where do you stand @Percy Jackson with your repeated argument of 'practicality'?

Devbrat Dandotiya - 3 weeks, 3 days ago

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@Devbrat Dandotiya My argument of 'practicality', is that when problems don't have specific information in them, you cannot make any assumptions. You will have to use real life information. You can't round off g to 10 if the value of gravitational acceleration constant isn't given. You'll have to use 9.81 m/s^2, so in the same way, you can't assume that welding is costlier as it is inclusive of breaking. Anyway, even if you reply to this comment, I will not reply, let's leave the topic.

Percy Jackson - 3 weeks, 3 days ago

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@Percy Jackson I have not assumed that welding is costlier as it includes breaking, I only tried to explain the obscurity in the problem by not assuming that it does not include breaking.

Devbrat Dandotiya - 3 weeks, 3 days ago

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@Percy Jackson But then at last I have to agree on that you might have been right all along which I kind of knew, I mean, why else the price of breaking would even be there when my solution doesn't even need that. It being there shows that breaking matters and that the price of welding is exclusive.

Devbrat Dandotiya - 3 weeks, 3 days ago

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@Devbrat Dandotiya I have to state, 10 cents to break a LINK instead of a whole chain. and to make all 12 pieces into a circle.

Half pass3 - 3 weeks, 3 days ago

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@Percy Jackson And 'magic fairies' are just an strawman argument.

Devbrat Dandotiya - 3 weeks, 3 days ago

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@Devbrat Dandotiya Well, you're being a strawman here :)

Percy Jackson - 3 weeks, 3 days ago

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@Percy Jackson Sure

Devbrat Dandotiya - 3 weeks, 3 days ago

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