Brain Teasers

[pgc01]

We have a solution. Oaktree is the winner!

I was careful when I asked the question, I did not ask "How can this be done", I asked "Is it possible?".

I gave a hint when Sundeep posted:

Need to get in more thinking done i guess

I answered:

Yes, that's the right direction.

In fact, you did not have to do any move, just think.

- When a rook passes by 2 squares in sequence they are always 1 white and 1 black.

- You remove 2 oposite corners and so you are left with 30 squares of one colour and 32 squares of the other colour.

- after the rook passes by 60 squares, it passed by 30 white an 30 black squares, there are 2 squares left but they are the same colour and so a rook could never pass by them one after the other.

Cheers
Thank you all

 

[schielrn]

And I kept reading is this possible, but then people started posted attemots, so I thought to myself that it must be possible. That was the best brain teaser yet.

 

[Sandeep Warrier]

.....
Now is anyone going to post the answer to the 5x5 grid with 5 dogs and 3 cats because I just can't work it out and it's making me feel stupid
....

Solution has already been posted... by Oaktree (i think)....

a recap:
5 dogs and 3 cats....

Excel Workbook
	A	B	C	D	E
1		dog	dog
2					cat
3	dog
4	dog	dog
5				cat	cat
Sheet1

Excel 2003

The 5 dogs can move in the area marked in yellow.... cats are safe....<input id="gwProxy" type="hidden"><!--Session data--><input *******="jsCall();" id="jsProxy" type="hidden"><input id="gwProxy" type="hidden"><!--Session data--><input *******="jsCall();" id="jsProxy" type="hidden">

 

[Sandeep Warrier]

This is not a brain teaser.... but tests speed of thought

http://www.cut-the-knot.org/Games/WolfRabbit.shtml
<input id="gwProxy" type="hidden"><!--Session data--><input *******="jsCall();" id="jsProxy" type="hidden">

 

[Hero-0952]

LoL! Nice :D I Like this!

 

[pgc01]

Hi

Here's another one. Much easier than the last and you may already know it. If you do, please don't post the answer immediately, not to spoil the fun for the others.

I's something like this:

Jack is leaving his building and Mary, an old friend he has not seen for years, is passing by.
Jack: Mary, hi, I haven't seen for so long!
Mary: Jack, hi. How nice to see you. How is Ann?
Jack: Ann is great, and so are the kids.
Mary: You have kids? What are their ages?
Jack: Yes, I have 3. Since you always like puzzles I'll tell you like this: do you see this number on the door of the building (both look at the number), well the sum of their ages is equal to this number and the product of the ages is 36.
Mary: Can you give me something more?
Jack: Come to think of it, yes, and you should remember it. Last time I saw you I was with Ann and our eldest daughter. Don't you remember?
Mary: Yes, how could I forget. I can even tell you when, it was just after I moved to my current apartment. Well, now I know the age of your kids.

Question: What's the ages of the 3 kids?

 

[Oaktree]

Even in the case of twins, one child is born (albeit minutes) before the other and is therefore technically older. With that in mind, I believe you've given us another "can't solve it" puzzle

 

[pgc01]

Even in the case of twins, one child is born (albeit minutes) before the other and is therefore technically older. With that in mind, I believe you've given us another "can't solve it" puzzle

No, I hadn't thought about it. But you are right. Let's say that when they last met Mary remebers that Jack only had 1 kid, 2 or 3 yours old. And I see that you already solved it!

 

[Sandeep Warrier]

Hmmmm....

Going by regular simultaneous equation rules... we have here 3 unknowns and 1 equation (product of ages = 36).... unless I'm missing something obvious....

 

[pgc01]

So that there are no confusions, Jack and Mary were having a perfectly normal conversation in English.

So when I ask someone how old is her child the aswer will be 4 years old and not something like 4 years 2 months and 1 day.