Tuesday Puzzle

3/2/10, 2:12 PM #1

Dan Donaldson
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Tuesday Puzzle

Dan Donaldson

I went to a local used book/magazine sale recently and found three back issues of some good woodworking magazines. This was not a formal "store", so the clerk was just using a calculator to figure out the amount owed. I took my three purchases up and watched as he entered them into his calculator. "Wait a minute" I said, "You just hit the multiply key rather than the addition key". He looked at his result and said "OOPS, however, it does not matter and the total cost is $5.70 in either case". What were the prices of the three magazines?

- - -

I have been woodworking for about 25 years now, and would consider myself an enthusiastic amateur. My claim to fame (or infamy) has always been fixing stuff. I spent time in the Air Force in the 60's then went to work as an electronic technician for civil service. I finally got my EE, and being fed up with the civil service nonsense, took a job with Ford Motor Company until I went with the split to Visteon last year. I got interested in music and started playing in a bluegrass band. I wanted a new guitar, and that kind of led me into woodworking. I bought some books, a few tools, and built a guitar. Luckily, I didn't know any better than to try that as a first ever project. I still play it when I get a chance, so it must not be too bad if it can live for over 20 years. After a stint in Mexico for my job, I moved into a new house and built a small shop. Since then I have been collecting tools and skills, probably more of the former than the latter ;-). Finding this site has done more for my skills and enjoyment than anything else. I have learned a lot and really enjoy the friendships that I have made here. I have been married to LOML (Lori) for 32 years now and have 6 kids. When they are all gone, I want to get a 1 bedroom house (so there is not room for them to move back in) and at least a 6 car heated/air conditioned garage for a shop. (Dream on...)

Re: Tuesday Puzzle

3/2/10, 2:28 PM #2

Steven Antonucci
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$1.90 is too easy- what am I missing?

Re: Tuesday Puzzle

3/2/10, 4:00 PM #3

Larry Barrett
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Re: Tuesday Puzzle

Larry Barrett

If I interpret "Wait a minute, you just hit the multiply key rather than the addition key" correctly, the third mag cost $2.00.

Re: Tuesday Puzzle

3/2/10, 5:58 PM #4

Dan Donaldson
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Doesn't work

Dan Donaldson

1.9X1.9X1.9 does not equal 5.70

They are multiplied together, not by 3.

- - -

I have been woodworking for about 25 years now, and would consider myself an enthusiastic amateur. My claim to fame (or infamy) has always been fixing stuff. I spent time in the Air Force in the 60's then went to work as an electronic technician for civil service. I finally got my EE, and being fed up with the civil service nonsense, took a job with Ford Motor Company until I went with the split to Visteon last year. I got interested in music and started playing in a bluegrass band. I wanted a new guitar, and that kind of led me into woodworking. I bought some books, a few tools, and built a guitar. Luckily, I didn't know any better than to try that as a first ever project. I still play it when I get a chance, so it must not be too bad if it can live for over 20 years. After a stint in Mexico for my job, I moved into a new house and built a small shop. Since then I have been collecting tools and skills, probably more of the former than the latter ;-). Finding this site has done more for my skills and enjoyment than anything else. I have learned a lot and really enjoy the friendships that I have made here. I have been married to LOML (Lori) for 32 years now and have 6 kids. When they are all gone, I want to get a 1 bedroom house (so there is not room for them to move back in) and at least a 6 car heated/air conditioned garage for a shop. (Dream on...)

Re: Tuesday Puzzle

3/2/10, 5:59 PM #5

Dan Donaldson
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Not my answer

Dan Donaldson

That is not one of the answers that I got, but that does not mean there is not one like that. Can you email me your solution?

- - -

I have been woodworking for about 25 years now, and would consider myself an enthusiastic amateur. My claim to fame (or infamy) has always been fixing stuff. I spent time in the Air Force in the 60's then went to work as an electronic technician for civil service. I finally got my EE, and being fed up with the civil service nonsense, took a job with Ford Motor Company until I went with the split to Visteon last year. I got interested in music and started playing in a bluegrass band. I wanted a new guitar, and that kind of led me into woodworking. I bought some books, a few tools, and built a guitar. Luckily, I didn't know any better than to try that as a first ever project. I still play it when I get a chance, so it must not be too bad if it can live for over 20 years. After a stint in Mexico for my job, I moved into a new house and built a small shop. Since then I have been collecting tools and skills, probably more of the former than the latter ;-). Finding this site has done more for my skills and enjoyment than anything else. I have learned a lot and really enjoy the friendships that I have made here. I have been married to LOML (Lori) for 32 years now and have 6 kids. When they are all gone, I want to get a 1 bedroom house (so there is not room for them to move back in) and at least a 6 car heated/air conditioned garage for a shop. (Dream on...)

Re: Tuesday Puzzle

3/2/10, 11:03 PM #6

Alex Y
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Answer (Don't read if you are trying)

Alex Y

This was a tough one. I think the prices were 1.25, 1.60, and 2.85. Sum $5.70 and product $5.70

Re: Tuesday Puzzle

3/3/10, 12:30 AM #7

Dan Donaldson
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;-)

- - -

I have been woodworking for about 25 years now, and would consider myself an enthusiastic amateur. My claim to fame (or infamy) has always been fixing stuff. I spent time in the Air Force in the 60's then went to work as an electronic technician for civil service. I finally got my EE, and being fed up with the civil service nonsense, took a job with Ford Motor Company until I went with the split to Visteon last year. I got interested in music and started playing in a bluegrass band. I wanted a new guitar, and that kind of led me into woodworking. I bought some books, a few tools, and built a guitar. Luckily, I didn't know any better than to try that as a first ever project. I still play it when I get a chance, so it must not be too bad if it can live for over 20 years. After a stint in Mexico for my job, I moved into a new house and built a small shop. Since then I have been collecting tools and skills, probably more of the former than the latter ;-). Finding this site has done more for my skills and enjoyment than anything else. I have learned a lot and really enjoy the friendships that I have made here. I have been married to LOML (Lori) for 32 years now and have 6 kids. When they are all gone, I want to get a 1 bedroom house (so there is not room for them to move back in) and at least a 6 car heated/air conditioned garage for a shop. (Dream on...)

Re: Tuesday Puzzle

3/3/10, 2:49 PM #8

Gary Smyth
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Re: Answer (Don't read if you are trying)

Gary Smyth

I see the answer but don't know how it was figured. Was it selective picking numbers and doing the math or is there a formula?

Re: Tuesday Puzzle

3/3/10, 6:16 PM #9

Alex Y
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Re: Answer (Don't read if you are trying)

Alex Y

No formula, but "guided" guessing.

Expressed in pennies, this problem comes out to

x+y+z = 570 and

x*y*z = 5,700,000

The rationale for the extra zeros took a little figuring, and I still can't effectively put it into words.

Factoring 5700000, I get 2^5*3*5^5*19.

It seemed like 19 was going to be the "problem child", and one of the prices was almost certainly a multiple of 5*19, or else we would have an unusual number of pennies to be able to multiply out and get 5.70.

Then I let excel do the grunt work as I looked at what it would mean if one price was $.95, $1.90, $2.85, $3.80, or $4.75

For each, I determined the required sum and product of the other two prices. At $2.85, the other two have to add to $2.85 and multiply out to $2.00.

$1.25 and $1.60 fit here. I actually let excel do a little more to find the two; let me know if you have questions. Unfortunately, I trashed the spreadsheet or I would offer to send it to you.

Re: Tuesday Puzzle

3/4/10, 3:40 PM #10

Steven Antonucci
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That's what I didn't get- product of prices...

Steven Antonucci

fire up the old brain real quick....

Re: Tuesday Puzzle

3/4/10, 3:54 PM #11

Steven Antonucci
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A quick run down a rathole

Steven Antonucci

I decided to look at this quikly, and figured that if I just set one of the items to $1, the other two would bave to total to $4.70. Unfortunately, the quadratic that results give me a solution that has a $.0056 rounding error at 3.26 and 1.44. So close to glory!

What if we just picked up a "take-a-penny" frm the counter?

S

Tuesday Puzzle

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