How would you solve this? (Fast reply needed)

[Alvaro Martín Gómez A.]

Hi everybody.

I've been asked to solve this puzzle as an assignment in my post-university program and I can't think of a solution:

I want to create a necklace from this chain, which is divided in four parts with three links each. Opening a link costs $25 and closing it costs another $25, but I only have $150. How can I create the necklace without spending extra money?

Your input is highly appreciated. Thank you in advance!

 

[NJL]

bump and subscribe

 

[FrizzleFry]

Weld?.. but I wish I actually new.

 

[jonathan_matos5]

leave two links open so you can put on or remove the necklace is my guess so you open and close two links for $100 and you open two links for $50. my solution only uses the $150 but it leaves a section of links not permanently attached.

 

[iamlowsound]

Open one link, put two different links from different sections into it. Then open both links on the end of the last section and put one on each end of two different sections. $150 spent and you have a necklace with three sections comprising the circle and one section hanging down.

lowsound

 

[Alvaro Martín Gómez A.]

my solution only uses the $150 but it leaves a section of links not permanently attached.

That's what I thought, but I don't think it's the answer.

 

[NJL]

you'll have two links hanging down from the necklace...

 

[arbitrary]

I can do it for $100, but whoever is wearing it must have a neck that will fit inside 6 links.

 

[jonathan_matos5]

spend $150 on a class to learn how to weld and cut metal

 

[iamlowsound]

I can do it for $100, but whoever is wearing it must have a neck that will fit inside 6 links.

I can do it for $50, but you need to be able to fit your neck into three links.

lowsound

 

[bongomania]

We do not know the length of each segment, and we do not know that all four segments must be used. Perhaps a "necklace" can consist of three of those segments.

 

[Alvaro Martín Gómez A.]

and we do not know that all four segments must be used.

That's what I've been thinking all the time, but I'm afraid I must assume that all links must be used.

 

[JansenW]

Take one set of 3-links. Open the center link and...

a. Detach the two end links from it. ($25)
b. Then insert any end links from two separate set of 3-links and close it. ($25) Giving a set of 7-links.

You should now have a set of 7 links, a set of 3 links and 2 single sinks. You should be able to figure out the rest for yourself.

 

[Sir Edward V]

Take one set of three links and set it aside the other three are sets 1, 2, and 3. Break each of the links in the set aside set, then take one of them and link together sets 1 & 2, take another to link 2 & 3, take another to connect 3 & 1.

BAM

hehe

(BTW that was 3 breaks and 3 connects for a total of 6, 6 times $25 = $150)

 

[NJL]

Take one set of three links and set it aside the other three are sets 1, 2, and 3. Break each of the links in the set aside set, then take one of them and link together sets 1 & 2, take another to link 2 & 3, take another to connect 3 & 1.

BAM

hehe

(BTW that was 3 breaks and 3 connects for a total of 6, 6 times $25 = $150)

awesome!!

 

[Cerb]

Take one set of 3-links. Open the center link and...

a. Detach the two end links from it. ($25)
b. Then insert any end links from two separate set of 3-links and close it. ($25) Giving a set of 7-links.

You should now have a set of 7 links, a set of 3 links and 2 single sinks. You should be able to figure out the rest for yourself.

This is the correct method. I was presented this puzzle once and it took me a good 45 minutes to figure out. Just PM if you need help after these steps.

 

[JansenW]

My solution is the same as Sir Edward's. He opened all the links at the same time. I just dealt with opening and closing one link at a time.

 

[Cerb]

My solution is the same as Sir Edward's. He opened all the links at the same time. I just dealt with opening and closing one link at a time.

That it is.

It's always a bad thing to reply before reading the rest of the thread.

 

[Sir Edward V]

That it is.

It's always a bad thing to reply before reading the rest of the thread.

I read the first post and figured it out, then read the thread hoping no one else answered it so I could have all the glory... Then I saw his answer and decided to post what I came up with anyways

And yeah, it is the same, just explained differently.

 

[JansenW]

I read the first post and figured it out, then read the thread hoping no one else answered it so I could have all the glory... Then I saw his answer and decided to post what I came up with anyways

And yeah, it is the same, just explained differently.

Your explanation was better.