Challenge your brains! Can you solve this problem?

[Redz]

I always liked this one (From Die Hard 3).  Not too difficult at all, but fun

To stop a bomb going off, McClane and Zeus have to measure out exactly four gallons of water from a fountain using a three gallon jug and a five gallon jug.

So how do you do it?

fill up the five gallon jug

pour 3 of it into the 3 gallon jug

and save 2 in the 5 gallon jug

dump out the 3 gallon jug

fill the 5 gallon jug back up and pour the 1 available gallon into the 3 gallon jug (leaving 4 in the 5 gallon jug)

whether I could think of that with the pressure a bomb exploding or not I don't know, but that's why I never had Hans Gruber after me.

[yall hate]

looks like you guys got both ways

[Roy Hobbs]

I always liked this one (From Die Hard 3).  Not too difficult at all, but fun

To stop a bomb going off, McClane and Zeus have to measure out exactly four gallons of water from a fountain using a three gallon jug and a five gallon jug.

So how do you do it?

Fill the 5 gallon jug.  Pour it into the 3 gallon jug.

That leaves 2 gallons in the big jug.  Empty the 3 gallon jug.  Fill it will the 2 gallons left in the big jug. 

Fill the 5 gallon jug.  Pour it into the 3 gallon jug, until it's full (don't spill any.)  You should be pouring exactly one gallon (since the small jug has two gallons already).

Since you've just poured 1 gallon from a 5 gallon jug, you're left with 4 gallons in the big jug.

[Redz]

Here's another one from class this weekend.  Using individual squares or combinations of squares, how many squares can you make on a checkerboard? (hint: it's more than a hundred-fifty)

[Roy Hobbs]

Doh!  Redz got it just before I did.  Too slow, yet again.

[Redz]

Doh!  Redz got it just before I did.  Too slow, yet again.

Oh, there were a few before me too.

[cdif911]

stare at this for a while

[Fan from VT]

how did you arrive at your answer VT?

I drew a pie charts and worked from the end to the beginning

I know from working with fractions of thirds (mostly from cooking, i think), that if something is 1/3 less, then if you take that something and add half of it back to it (or 150% of the something), you get the original. Do it 3 times, get 27!

In clearer terms, I just know looking at 8 that if you add half of it (4), you'll get a number that if you take 1/3 away, you end up with 8.

After I thought the answer was 27, I double checked by running through forwards.

[Fan from VT]

Here's another one from class this weekend.  Using individual squares or combinations of squares, how many squares can you make on a checkerboard? (hint: it's more than a hundred-fifty)

i get 204

[Roy Hobbs]

Here's another one from class this weekend.  Using individual squares or combinations of squares, how many squares can you make on a checkerboard? (hint: it's more than a hundred-fifty)

204.

(And sadly, I had to manually start counting squares until I figured out the pattern, which is 8^2 + 7^2 + 6^2 + 5^2 + 4^2 + 3^2 + 2^2 + 1^2)

[Redz]

yup 204

[Redz]

Hey math people, I need to a come up with a math problem to present to my class.  Something along the same level as the last couple I posted on here (nothing insanely difficult).  Anyone have any favorites?

In the mean time here's one that took me a couple of minutes to figure out, but was a big DERRR once I did.

During the game show "Pick A Door" the contestant gets to choose one of the doors on the stage. Behind two of the doors is a bucket of dirt, behind the 3rd is some fabulous prize (make up your own) Bucko, the host, opens one of the two doors the contestant did not choose.  The door he opens always reveals a bucket of dirt.  The contestant is then given the option of sticking with his original choice, or switching his pick to the unrevealed door.

If you were the contestant would you stick with your original pick or switch?  Why?

[wdleehi]

Hey math people, I need to a come up with a math problem to present to my class.  Something along the same level as the last couple I posted on here (nothing insanely difficult).  Anyone have any favorites?

In the mean time here's one that took me a couple of minutes to figure out, but was a big DERRR once I did.

During the game show "Pick A Door" the contestant gets to choose one of the doors on the stage. Behind two of the doors is a bucket of dirt, behind the 3rd is some fabulous prize (make up your own) Bucko, the host, opens one of the two doors the contestant did not choose.  The door he opens always reveals a bucket of dirt.  The contestant is then given the option of sticking with his original choice, or switching his pick to the unrevealed door.

If you were the contestant would you stick with your original pick or switch?  Why?

Can I tell you one later?  I have a ton, I just can't remember one of the top of my head right now. 

[Rondo2287]

Suppose you had eight billiard balls, the recruiter began. One of them is slightly heavier, but the only way to tell is by putting it on a scale against the others. What's the fewest number of times you'd have to use the scale to find the heavier ball?

[fairweatherfan]

Hey math people, I need to a come up with a math problem to present to my class.  Something along the same level as the last couple I posted on here (nothing insanely difficult).  Anyone have any favorites?

In the mean time here's one that took me a couple of minutes to figure out, but was a big DERRR once I did.

During the game show "Pick A Door" the contestant gets to choose one of the doors on the stage. Behind two of the doors is a bucket of dirt, behind the 3rd is some fabulous prize (make up your own) Bucko, the host, opens one of the two doors the contestant did not choose.  The door he opens always reveals a bucket of dirt.  The contestant is then given the option of sticking with his original choice, or switching his pick to the unrevealed door.

If you were the contestant would you stick with your original pick or switch?  Why?

You switch.  When you made your original pick, you had a 1/3 chance of being correct, and a 2/3 chance of being wrong. Because the door that's eliminated is always a wrong response, that 2/3 chance now only applies to the remaining door that you didn't pick.