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PendO
07-15-2006, 01:54 AM
A manufacture has 5 machines that make "widgets" ... the widgets are all supposed to weigh 10 grams ... one of the machines is producing widgets that weigh 9 grams and needs to be fixed... you are given a scale and a 5 gallon bucket to weigh the widgets (the scale is calibrated to zero with the empty bucket) ... you can use the scale once (only once) ... how do you determine which machine is producing the wrong weight widgets?

JimN
07-15-2006, 08:46 AM
You put one widget in at a time and note the weight. When you see an increase of nine grams, you know which machine needs to be fixed. This only works if you can put the bucket on the scale once.

Kell
07-15-2006, 09:33 AM
PendO, now that you've passed the WSBA exam, are you now studying for a LLM with these types of brain teasers? ;) I'm with JimN on this one. Also reminds me of a saying that I frequently state about law school. My undergrad was in engineering and up until law school 2 + 2 always equals 4. After law school, 2 + 2 is anything between 1 and 10! :D

Datdude
07-15-2006, 12:18 PM
That was too easy:D

PendO
07-15-2006, 03:13 PM
You put one widget in at a time and note the weight. When you see an increase of nine grams, you know which machine needs to be fixed. This only works if you can put the bucket on the scale once.

you can only use the scale once .... sorry ... your way requrires using the scale for multiple readings ...

Kell, I thought it was easy too, then my brother (Computer Science) had to explain the directions ... it was a question a friend of his got at an interview ... you had 30 minutes to answer it ... needless to say, it took me more than 30 min when my brother gave me the question.

JimN
07-15-2006, 03:32 PM
Unless the person using the scale gets lucky, chance is the only way to get the light one. That being the case, two or more of the widgets could be put into the bucket and weighed. This way, it's in one group or the other and the scale would reflect that.

Another way is to look at the widgets and see if there are any flaws or voids. If something is missing 10% of it's normal amount of material, it could be visible.

What kind of scale is this? Flat bed with a display or is it a balance with weights? The one-time use is the only rule in this?

PendO
07-15-2006, 03:35 PM
Unless the person using the scale gets lucky, chance is the only way to get the light one. That being the case, two or more of the widgets could be put into the bucket and weighed. This way, it's in one group or the other and the scale would reflect that.

What kind of scale is this? Flat bed with a display or is it a balance with weights? The one-time use is the only rule in this?

you can put as many or as few of widgets into the bucket when you weigh it ... it is a digital scale, but it will only give you one weight reading. The weight of the bucket is negated by the use of the tare feature.

PendO
07-15-2006, 03:42 PM
the bucket will fit anywhere from 1 widget to a few million widgets

ChrisJR10
07-15-2006, 04:19 PM
Fill the bucket with 15 widgets ... 1 from machine #1, 2 from #2, etc. The difference of weight in oz from what it should be (150) will give you the defective machine. (ie. if its machine 5, 5 widgets only weigh 9 oz so the total weight of the 15 widgets will be 145 oz.) I hope that this is the wrong answer because if I had 30 mins to answer, I would be bored out of my mind for 29. My question is, what is a widget???

PendO
07-15-2006, 04:44 PM
Fill the bucket with 15 widgets ... 1 from machine #1, 2 from #2, etc. The difference of weight in oz from what it should be (150) will give you the defective machine. (ie. if its machine 5, 5 widgets only weigh 9 oz so the total weight of the 15 widgets will be 145 oz.) I hope that this is the wrong answer because if I had 30 mins to answer, I would be bored out of my mind for 29. My question is, what is a widget???

yer right...............

As for what a widget is ... whenever we had a torts question in school it was always about some "widget" or "widget machine" ... I think the original question my brother told me had to do with nails ... its just a question to see if you can synthesize an algebra equation.

JimN
07-15-2006, 08:19 PM
Got it in 1 minute but missed the units- they were 9 or 10 grams, not ounces. Do you work at NASA on the Mars Rovers?

You never took econ? I thought they still used widgets as universally unnamed manufactured goods.

Good answer, though.