Caro and the three kids arrived yesterday; this morning was a little nuts. I was trying to work on my class project due next week. Between kids running around and asking questions, one broken glass, one missing cat and making breakfast, I didn't get much done. I'm having fun.
The puzzle and question (again):
You have twelve coins, one of which is a fake. It is a fake because it weighs more or less than the other eleven coins. (You do not know whether it weighs more, or less.) You have a very old balance that indicates, when coins are placed on each of the two platters, which set of coins is heavier. Can you find the fake coin in three weighings?
Answer:
Divide the 12 coins into 4 sets of 3 coins. We'll call these sets A, B, C and D. Weigh A and B. Without loss of generality, let us suppose that A and B differ in weight. Remove a coin from A, and from B; put these two coins aside. Take a coin from A and swap it with a coin from B. Reweigh the two (smaller) sets. If their weights are equal then the fake coin is one of the two you removed. If nothing changes then the fake coin is one of the coins you didn't touch. If the weight reading is reversed (lighter becomes heavier and heavier becomes lighter) then the fake coin is one of the swapped coins. For the pair of coins identified as containing a fake, weigh one of its coins against any know valid coin. If these two are of equal weight then the fake is other of the idenified pair, otherwise the fake is the coin (of the identified pair) that was just weighed.
Saturday, June 23, 2007
Friday, June 15, 2007
You're actually reading this
People are actually reading the blog. Wow!
For all the Newfs still reading this, if you see my Master's supervisor tell him that he should work on my thesis. In a related note, I've delayed my entry date to UVic until September 1st.
In this blog, I reveal most of Veronica's dark personal secrets. I'll tell you the remaining secrets next time. This should make next week exciting. Although... Veronica never reads the blog. You're still reading; don't you have personal ethics? I'll give you the answer to the puzzle instead.
I was about to publish the answer to the Coin puzzle when I realized that I gave the wrong hint. The hint was supposed to be 4 piles of 3 coins. I guess, I'll publish the answer next week.
That makes this week's post even more boring than it was going to be. More concrete and irrefutable evidence that I should be doing this PhD while wrestling a polar bear. Now that, would make this blog exciting!
For all the Newfs still reading this, if you see my Master's supervisor tell him that he should work on my thesis. In a related note, I've delayed my entry date to UVic until September 1st.
In this blog, I reveal most of Veronica's dark personal secrets. I'll tell you the remaining secrets next time. This should make next week exciting. Although... Veronica never reads the blog. You're still reading; don't you have personal ethics? I'll give you the answer to the puzzle instead.
I was about to publish the answer to the Coin puzzle when I realized that I gave the wrong hint. The hint was supposed to be 4 piles of 3 coins. I guess, I'll publish the answer next week.
That makes this week's post even more boring than it was going to be. More concrete and irrefutable evidence that I should be doing this PhD while wrestling a polar bear. Now that, would make this blog exciting!
Friday, June 8, 2007
A hint
Rather than the answer, I'll give you a hint: 3 piles of 4 coins.
I MAY end up in Germany for 6 months. I guess Veronica can come too.
I encourage people to comment on the blog items. Just click on the word "comment" below each blog item.
I MAY end up in Germany for 6 months. I guess Veronica can come too.
I encourage people to comment on the blog items. Just click on the word "comment" below each blog item.
Tuesday, June 5, 2007
Enough from Neil already!!!
I'm not really sure what to write in a blog. But I have to say that I am getting really annoyed with the fact that Neil won't stop bugging me that I will lose my place as social secretary if I don't keep in contact with everyone. Little does he know, that I have been sending emails to people, but perhaps doing this will keep him off my back!!!
So I was thinking that I would talk about our car adventures. More specifically the adventures of trying to arrange insurance and getting the plates on the car.....
This whole car thing, has been incredibly time consuming! This is because when you move to BC lots of things have to be done, and they must all be done within the first month, otherwise car insurance gets cancelled, and no insurance no driving.... which means the weekends could have the potential to be quite boring..... so the adventure of "getting BCed" began.
We needed to have an oil change, because driving across the country does rack up a few kms, as well as new tires, and a brake check.... which by the way turned out to be a brake change in the front!!! :) We found a garage thanks to one of my coworkers, and set off to have all of the repairs done. BUT, after all of this is done, there is also the requirement of having an inspection. Now on a sidenote, all of you have seen our car, I must say that newer cars shouldn't have to have this inspection done.... I mean the cars all come from the same plant in Asia somewhere, no matter where they ship them.... but because we had an "out of province" car... the inspection was required! So we then had that done..... and once all of that came to a close we had to have plates (yes with an s)... which I must add is hard to do when you only have place for one plate....... did I mention we had to go back to the garage a third time!!!!
So getting back to the insurance part of the story.... we were required to give our Newfoundland plate to the ICBC people. (apparently you aren't supposed to keep your old licence plate )... this turned out to be quite the task.... because when you live in NFLD, there is lots of salt in the air.... and salt makes things rust..... and I think most of us can see where this is going...... YES that is right... the plate decided to be rusted to the back of the car.... which meant that we couldn't remove it to give to the insurance people. They pulled out a box of tools, but to no avail the rust wasn't going to let us win!!!
So we decided, "if we have the right type of screwdriver, maybe it will work".... so we went to Wal-Marde to get a screwdriver.... and it so happens that the woman that was helping us was married to a man from a little island that we had just left.... yes, her husband was from The Rock..... coincidence, I think not.... them newfs b'y they're everywhere!!!!! :)
Anyways we ended up returning the screwdriver, because the f%$#*&@ screws would not come off.... the rust just didn't want to let go!!!! Needless to say we had to bring the plate back to ICBC the next day, after Neil fought with it at home!!!
But it was an interesting adventure... and now we have 2 plates on the car, and we are allowed to drive it and play bumper cars if we really want to!!!! :)
I'll try and write again soon!!!! :)
So I was thinking that I would talk about our car adventures. More specifically the adventures of trying to arrange insurance and getting the plates on the car.....
This whole car thing, has been incredibly time consuming! This is because when you move to BC lots of things have to be done, and they must all be done within the first month, otherwise car insurance gets cancelled, and no insurance no driving.... which means the weekends could have the potential to be quite boring..... so the adventure of "getting BCed" began.
We needed to have an oil change, because driving across the country does rack up a few kms, as well as new tires, and a brake check.... which by the way turned out to be a brake change in the front!!! :) We found a garage thanks to one of my coworkers, and set off to have all of the repairs done. BUT, after all of this is done, there is also the requirement of having an inspection. Now on a sidenote, all of you have seen our car, I must say that newer cars shouldn't have to have this inspection done.... I mean the cars all come from the same plant in Asia somewhere, no matter where they ship them.... but because we had an "out of province" car... the inspection was required! So we then had that done..... and once all of that came to a close we had to have plates (yes with an s)... which I must add is hard to do when you only have place for one plate....... did I mention we had to go back to the garage a third time!!!!
So getting back to the insurance part of the story.... we were required to give our Newfoundland plate to the ICBC people. (apparently you aren't supposed to keep your old licence plate )... this turned out to be quite the task.... because when you live in NFLD, there is lots of salt in the air.... and salt makes things rust..... and I think most of us can see where this is going...... YES that is right... the plate decided to be rusted to the back of the car.... which meant that we couldn't remove it to give to the insurance people. They pulled out a box of tools, but to no avail the rust wasn't going to let us win!!!
So we decided, "if we have the right type of screwdriver, maybe it will work".... so we went to Wal-Marde to get a screwdriver.... and it so happens that the woman that was helping us was married to a man from a little island that we had just left.... yes, her husband was from The Rock..... coincidence, I think not.... them newfs b'y they're everywhere!!!!! :)
Anyways we ended up returning the screwdriver, because the f%$#*&@ screws would not come off.... the rust just didn't want to let go!!!! Needless to say we had to bring the plate back to ICBC the next day, after Neil fought with it at home!!!
But it was an interesting adventure... and now we have 2 plates on the car, and we are allowed to drive it and play bumper cars if we really want to!!!! :)
I'll try and write again soon!!!! :)
Friday, June 1, 2007
The Coins Puzzle
This post will probably appeal to Sparling and Luke. Maybe others will enjoy this too. I'll post the answer next week.
You have twelve coins, one of which is a fake. It is a fake because it weighs more or less than the other eleven coins. (You do not know whether it weighs more, or less.) You have a very old balance that indicates, when coins are placed on each of the two platters, which set of coins is heavier.
(easy) Can you find the fake coin?
(more difficult) Can you find the fake coin in three weighings?
If you cheat and find the answer on the Internet, shame on you!
You have twelve coins, one of which is a fake. It is a fake because it weighs more or less than the other eleven coins. (You do not know whether it weighs more, or less.) You have a very old balance that indicates, when coins are placed on each of the two platters, which set of coins is heavier.
(easy) Can you find the fake coin?
(more difficult) Can you find the fake coin in three weighings?
If you cheat and find the answer on the Internet, shame on you!
Subscribe to:
Posts (Atom)