Brain Teaser No 1
Posted by: Don Atkinson on 16 November 2001
THE EXPLORER
An explorer set off on a journey. He walked a mile south, a mile east and a mile north. At this point he was back at his start. Where on earth was his starting point? OK, other than the North Pole, which is pretty obvious, where else could he have started this journey?
Cheers
Don
Posted on: 15 November 2002 by Dan M
Don,
I think I have a viable scheme if you allow a measurement to be off scale - is that allowed?
-Dan
I think I have a viable scheme if you allow a measurement to be off scale - is that allowed?
-Dan
Posted on: 16 November 2002 by Don Atkinson
Dan,
The object is to identify the 180s, 250s and 135s and if knowing that "something" weighs MORE THAN 30 kg helps, then this is allowed.
We will assume that the scales will not be damaged by large weights, say up to 100kg, but the only information available above 30kg is that it is more than 30kg.
BTW, from the information you have given, I am certain you have a valid scheme.
Cheers
Don
The object is to identify the 180s, 250s and 135s and if knowing that "something" weighs MORE THAN 30 kg helps, then this is allowed.
We will assume that the scales will not be damaged by large weights, say up to 100kg, but the only information available above 30kg is that it is more than 30kg.
BTW, from the information you have given, I am certain you have a valid scheme.
Cheers
Don
Posted on: 16 November 2002 by Dan M
quote:
BTW, from the information you have given, I am certain you have a valid scheme.
Ah, very good -- I'll wait until a few others have had a chance to see the puzzle before posting.
cheers,
Dan
Posted on: 16 November 2002 by Don Atkinson
Dan
I'll wait until ........
What a jolly decent chap you are. Remember, the weekend over here leaves very few people at home surfing the net, so it could be Monday before the bright sparks return to their keyboards......
Cheers
Don
I'll wait until ........
What a jolly decent chap you are. Remember, the weekend over here leaves very few people at home surfing the net, so it could be Monday before the bright sparks return to their keyboards......
Cheers
Don
Posted on: 18 November 2002 by Matthew T
One
Posted on: 18 November 2002 by steved
Don,
I assume you are allowed to open the crates.
If so, I agree that the answer is 1.
Steve D
I assume you are allowed to open the crates.
If so, I agree that the answer is 1.
Steve D
Posted on: 18 November 2002 by Paul Ranson
135s only have one pair of speaker sockets. So I'll take those and you can weigh the remainder as many times as you want...
Paul
Paul
Posted on: 18 November 2002 by Matthew T
Paul,
One is still the answer.
Matthew
One is still the answer.
Matthew
Posted on: 18 November 2002 by Don Atkinson
Dan
"if you allow a measurement to be off scale" we do.
"I'll wait until a few others have had a chance" Now's your chance.
Mathew "one" Nows your chance to explain
Steved "I assume you are allowed to open the crates" you most certainly are.
Paul R "135s only have one pair of speaker sockets. So I'll take those" not before you describe the system of weighing you won't.
Can I suggest a time, say 22.00 hrs GMT at which you ALL post your solutions, including me and we'll vote on who's is the best?
I find that if I pre-type my entries in Word then I can 'paste' them into the forum pretty quickly at a predetermined time.
Ok, I agree is incredably nerdy, geeky, pathetic, even sad..........so 22.00 hrs it is, unless someone shouts otherwise....
Cheers
Don
"if you allow a measurement to be off scale" we do.
"I'll wait until a few others have had a chance" Now's your chance.
Mathew "one" Nows your chance to explain
Steved "I assume you are allowed to open the crates" you most certainly are.
Paul R "135s only have one pair of speaker sockets. So I'll take those" not before you describe the system of weighing you won't.
Can I suggest a time, say 22.00 hrs GMT at which you ALL post your solutions, including me and we'll vote on who's is the best?
I find that if I pre-type my entries in Word then I can 'paste' them into the forum pretty quickly at a predetermined time.
Ok, I agree is incredably nerdy, geeky, pathetic, even sad..........so 22.00 hrs it is, unless someone shouts otherwise....
Cheers
Don
Posted on: 18 November 2002 by Dan M
Given crates A, B, and C, weigh 3 amps for crate A and 1 amp from crate B.
Possible totals are:
3*6 + 7 = 25 kg => C = 135's, B = 250's , A = 180's
3*6 + 8 = 26 kg => B = 135's, C = 250's , A = 180's
3*7 + 6 = 27 kg => C = 135's, A = 250's , B = 180's
3*7 + 8 = 29 kg => B = 135's, A = 250's , C = 180's
3*8 + 6 = 30 kg => A = 135's, C = 250's , B = 180's
3*8 + 7 > 30 kg => A = 135's, B = 250's , C = 180's
Not very elegent, but it gets the job done.
-Dan
Possible totals are:
3*6 + 7 = 25 kg => C = 135's, B = 250's , A = 180's
3*6 + 8 = 26 kg => B = 135's, C = 250's , A = 180's
3*7 + 6 = 27 kg => C = 135's, A = 250's , B = 180's
3*7 + 8 = 29 kg => B = 135's, A = 250's , C = 180's
3*8 + 6 = 30 kg => A = 135's, C = 250's , B = 180's
3*8 + 7 > 30 kg => A = 135's, B = 250's , C = 180's
Not very elegent, but it gets the job done.
-Dan
Posted on: 18 November 2002 by steved
Dan,
I was just about to post my solution when I noticed you had beaten me to it! Mine was identical to yours.
Steve D
I was just about to post my solution when I noticed you had beaten me to it! Mine was identical to yours.
Steve D
Posted on: 19 November 2002 by Matthew T
Same method. Can't see there is any other way.
Matthew
Matthew
Posted on: 19 November 2002 by Matthew T
A number of forum memebers have been frequenting a riddles post for a number of days now and have been keeping track of scores.
Each forum member has scored 100 points, with a 100 points being scored on each day the post has been running. Coincidentally a total of 100 riddles have also been solved.
Scoring works like this. Each member gets one point for the first riddle they solve each day, two points for the second and so on.
The first day saw Don weighing with a mighty 9 riddles and Paul managed a healthy 7. d marsh finsihed the game with 6 riddles on the final day, however he had forgotten what he had scored on the previous days but after a moment (he knew his total was 100) he managed to figure out what he had scored on day one.
What had he scored?
Each forum member has scored 100 points, with a 100 points being scored on each day the post has been running. Coincidentally a total of 100 riddles have also been solved.
Scoring works like this. Each member gets one point for the first riddle they solve each day, two points for the second and so on.
The first day saw Don weighing with a mighty 9 riddles and Paul managed a healthy 7. d marsh finsihed the game with 6 riddles on the final day, however he had forgotten what he had scored on the previous days but after a moment (he knew his total was 100) he managed to figure out what he had scored on day one.
What had he scored?
Posted on: 19 November 2002 by steved
MATTHEW
He scored 6 points (3 riddles) on the first day.
STEVE D
He scored 6 points (3 riddles) on the first day.
STEVE D
Posted on: 19 November 2002 by Matthew T
steved hit the nail on the head. Anyone want to explain why...
Matthew
Matthew
Posted on: 19 November 2002 by Don Atkinson
Apologies, but I fell asleep last night and missed the deadline for posting replies. FWIW mine is like others ie
Power Weights
We will take 3 amps from one box and one amp from either of the other two boxes, making four amps to be weighed, altogether.
The possible combined weight of these four amps will be as follows and will enable us to determine which box is which
3 at 6 kg + 1 at 7 kg = 25 kg
3 at 6 kg + 1 at 8 kg = 26 kg
3 at 7 kg + 1 at 6 kg = 27 kg
3 at 7 kg + 1 at 8 kg = 29 kg
3 at 8 kg + 1 at 6 kg = 30 kg
3 at 8 kg + 1 at 7 kg = >30 kg
Cheers
Don
Power Weights
We will take 3 amps from one box and one amp from either of the other two boxes, making four amps to be weighed, altogether.
The possible combined weight of these four amps will be as follows and will enable us to determine which box is which
3 at 6 kg + 1 at 7 kg = 25 kg
3 at 6 kg + 1 at 8 kg = 26 kg
3 at 7 kg + 1 at 6 kg = 27 kg
3 at 7 kg + 1 at 8 kg = 29 kg
3 at 8 kg + 1 at 6 kg = 30 kg
3 at 8 kg + 1 at 7 kg = >30 kg
Cheers
Don
Posted on: 20 November 2002 by Dan M
Matthew,
Spent a good hour last night on your riddle teaser and got nowhere.
Obviously I'm missing something here.
cheers,
Dan
Spent a good hour last night on your riddle teaser and got nowhere.
Obviously I'm missing something here.
cheers,
Dan
Posted on: 20 November 2002 by Paul Ranson
The riddle problem has much unnecessary (dis)information.
You're only interested in the first day, you know what everybody else scored, you know the total scored, the rest follows...
Paul
You're only interested in the first day, you know what everybody else scored, you know the total scored, the rest follows...
Paul
Posted on: 20 November 2002 by Don Atkinson
Paul R very helpfully outlined the start of solving Mathew's riddle but I think there a few delicate steps between the rest follows...and the answer!
So you might like to try the 'stocking filler' that follows whilst musing on the various combinations of riddled scores
Cheers
Don
So you might like to try the 'stocking filler' that follows whilst musing on the various combinations of riddled scores
Cheers
Don
Posted on: 20 November 2002 by Don Atkinson
A mere 'stocking filler' to while away the time whilst musing on Mathew's riddled scores....
Choose any 3-digit number and write it down twice to form a 6-digit number eg 267267. Divide this 6-digit number by three prime numbers, thereby reducing the 6-digit number to the original 3-digit number.
What are the three prime numbers ?
Cheers
Don
Choose any 3-digit number and write it down twice to form a 6-digit number eg 267267. Divide this 6-digit number by three prime numbers, thereby reducing the 6-digit number to the original 3-digit number.
What are the three prime numbers ?
Cheers
Don
Posted on: 20 November 2002 by Paul Ranson
7, 11, 13?
That's quite profound!
Paul
That's quite profound!
Paul
Posted on: 21 November 2002 by Matthew T
I get the same answer.
I wouldn't say profound though!
Matthew
I wouldn't say profound though!
Matthew
Posted on: 21 November 2002 by Rockingdoc
I'm going to tell your employers about the lot of you.
malcolm
malcolm

Posted on: 22 November 2002 by Don Atkinson
I wouldn't say profound though!
I'm hurt !
Cheers
Don
I'm hurt !
Cheers
Don
Posted on: 25 November 2002 by Matthew T
You are asking us to solve the following equation.
(1000m + m) / x = m
which means x = 1001
That x exists and is an integer implies that it can be divided by prime numbers, that they are in sequence is somewhat profound I guess.
Matthew
(1000m + m) / x = m
which means x = 1001
That x exists and is an integer implies that it can be divided by prime numbers, that they are in sequence is somewhat profound I guess.
Matthew