# Fun math problem

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#### memo

##### Golden Member
Originally posted by: OdiN
Originally posted by: Demon-Xanth
1000

Take 1000 to the end, walk back, eat the other 2000
Can't do that. Have to eat one each KM he walks.
Does he HAVE to eat DURING the walk? The riddle doesn't explictly state that he has to eat during the walk. So he takes 1000 on his back, walks 1000km, drops off the balls, then comes back. He's walked 2000km roundtrip so he can eat 2000 at "home" (start point) and be happy.

nvm

#### TecHNooB

##### Diamond Member
Originally posted by: memo
Originally posted by: OdiN
Originally posted by: Demon-Xanth
1000

Take 1000 to the end, walk back, eat the other 2000
Can't do that. Have to eat one each KM he walks.
Does he HAVE to eat DURING the walk? The riddle doesn't explictly state that he has to eat during the walk. So he takes 1000 on his back, walks 1000km, drops off the balls, then comes back. He's walked 2000km roundtrip so he can eat 2000 at "home" (start point) and be happy.
Yes, it's during the walk. One at a time.

#### makken

##### Golden Member
hmm
622 using kmc's method

EDIT: opps, not odin

600

#### OdiN

##### Banned
Originally posted by: TecHNooB
Originally posted by: OdiN
Originally posted by: TecHNooB
No right answers yet, keep trying!
My answer is correct. Others probably as well.

If you want to post a real problem, go ahead. But there are too many holes in your existing one.
Tell me about it, ill clear it up.
You aren't specifying if he has to eat during the walk. You never said you can or cannot drop stuff off and pick them up later. You don't take large grues into account.

#### KLin

##### Lifer
http://www.urch.com/forums/gma...ng/28049-elephant.html

Another try

0-------P1-------P2--------------1000

The optimum condition would be to have a multiple of 2000 bananas at P1 and 1000 bananas at P2 since the lousy creature can carry only 1000kg at a time

0 to P1: 2 round trips and 1 one-way trip leaving us with 2000 bananas at P1. i.e. 5*P1=1000 => P1=200 Km

P1 to P2: 1 round trip and 1 one-way trip leaving us with 1000 bananas at P2.
i.e. 3*(P2-P1) = 1000 => P2-P1 = 1000/3 => P2 = 1600/3

At P2 we have 1000 bananas and (3000-1600)/3 = 1400/3 km to go

So at the 1000Km mark we are left with 1600/3 bananas.

I still say kill and cook the elephant and have a feast.

#### TecHNooB

##### Diamond Member
Originally posted by: OdiN
Originally posted by: TecHNooB
Originally posted by: OdiN
Originally posted by: TecHNooB
No right answers yet, keep trying!
My answer is correct. Others probably as well.

If you want to post a real problem, go ahead. But there are too many holes in your existing one.
Tell me about it, ill clear it up.
You aren't specifying if he has to eat during the walk. You never said you can or cannot drop stuff off and pick them up later. You don't take large grues into account.
It was meant to be semi hazy You're supposed to figure that out yourself. It starts out more like a riddle and ends in a math question. Grue?

#### OdiN

##### Banned
Originally posted by: memo
Originally posted by: OdiN
Originally posted by: Demon-Xanth
1000

Take 1000 to the end, walk back, eat the other 2000
Can't do that. Have to eat one each KM he walks.
Does he HAVE to eat DURING the walk? The riddle doesn't explictly state that he has to eat during the walk. So he takes 1000 on his back, walks 1000km, drops off the balls, then comes back. He's walked 2000km roundtrip so he can eat 2000 at "home" (start point) and be happy.
It doesn't state that you can or cannot drop stuff off either. Also what if he has dumbo ears and flies, then he wouldn't be walking so wouldn't have to eat any?

Stupid crap like this is why this is not a math problem and more of a riddle.

If you want a math problem, it needs to be concise and specific as to what can and cannot be done.

#### OdiN

##### Banned
Originally posted by: TecHNooB
Originally posted by: OdiN
Originally posted by: TecHNooB
Originally posted by: OdiN
Originally posted by: TecHNooB
No right answers yet, keep trying!
My answer is correct. Others probably as well.

If you want to post a real problem, go ahead. But there are too many holes in your existing one.
Tell me about it, ill clear it up.
You aren't specifying if he has to eat during the walk. You never said you can or cannot drop stuff off and pick them up later. You don't take large grues into account.
It was meant to be semi hazy You're supposed to figure that out yourself. It starts out more like a riddle and ends in a math question. Grue?
I'll just be hazy when describing something to an engineer so that when the bridge is built the traffic on it collapses and hundreds of people die.

Call it a riddle if you want to be hazy. Not a math problem.

#### TecHNooB

##### Diamond Member
Originally posted by: OdiN
Originally posted by: TecHNooB
Originally posted by: OdiN
Originally posted by: TecHNooB
Originally posted by: OdiN
Originally posted by: TecHNooB
No right answers yet, keep trying!
My answer is correct. Others probably as well.

If you want to post a real problem, go ahead. But there are too many holes in your existing one.
Tell me about it, ill clear it up.
You aren't specifying if he has to eat during the walk. You never said you can or cannot drop stuff off and pick them up later. You don't take large grues into account.
It was meant to be semi hazy You're supposed to figure that out yourself. It starts out more like a riddle and ends in a math question. Grue?
I'll just be hazy when describing something to an engineer so that when the bridge is built the traffic on it collapses and hundreds of people die.

Call it a riddle if you want to be hazy. Not a math problem.
What kind of engineer are you?

#### KMc

##### Golden Member
Originally posted by: KLin
http://www.urch.com/forums/gma...ng/28049-elephant.html

Another try

0-------P1-------P2--------------1000

The optimum condition would be to have a multiple of 2000 bananas at P1 and 1000 bananas at P2 since the lousy creature can carry only 1000kg at a time

0 to P1: 2 round trips and 1 one-way trip leaving us with 2000 bananas at P1. i.e. 5*P1=1000 => P1=200 Km

P1 to P2: 1 round trip and 1 one-way trip leaving us with 1000 bananas at P2.
i.e. 3*(P2-P1) = 1000 => P2-P1 = 1000/3 => P2 = 1600/3

At P2 we have 1000 bananas and (3000-1600)/3 = 1400/3 km to go

So at the 1000Km mark we are left with 1600/3 bananas.

I still say kill and cook the elephant and have a feast.
Damn, missed it by 33. So the only real question I have left is what did you google to come up with this?

#### poopygood

##### Senior member
don't remember that question on the GMAT

#### DrPizza

##### Administrator Elite Member Goat Whisperer
Originally posted by: TuxDave
I ended up with 500.

1) Picks up 1000, goes 250km, drops off 500 and goes home empty when he arrives.
2) Picks up 1000, goes 250km, picks up another 250, goes 250km drops off 500, goes back 250, picks up 250, goes back home empty when he arrives.
3) Picks up 1000, goes 500km, picks up 500, goes 500km, delivers 500.
Sounds good to me.

#### crystal

##### Platinum Member
500.
First trip - he carries 1000 ballz and travel to 250km. - he drops 500 there and goes back (0 ball). Another 1000 ballz to 250 km, pick up 250 ballz (250 left) and cont. to travel to 500km mark. Drops 500 ballz there (250 ballz left) and travel backs to where he left 250 ballz at 250km mark. Back to starting place with 0 ballz. Get the last 1000 ballz travel to 500km. pick up 500 ballz there (500 + 500 = 1000 ballz). finish the rest of 500km. got 500 ballz left.

let just say I type too slow.

#### Safeway

##### Lifer
53.333 ... Repeating, of course.

#### LordSnailz

##### Diamond Member
Originally posted by: DrPizza
Originally posted by: TuxDave
I ended up with 500.

1) Picks up 1000, goes 250km, drops off 500 and goes home empty when he arrives.
2) Picks up 1000, goes 250km, picks up another 250, goes 250km drops off 500, goes back 250, picks up 250, goes back home empty when he arrives.
3) Picks up 1000, goes 500km, picks up 500, goes 500km, delivers 500.
Sounds good to me.
yup, that's what I got too

#### sactoking

##### Diamond Member
Originally posted by: KLin
http://www.urch.com/forums/gma...ng/28049-elephant.html

Another try

0-------P1-------P2--------------1000

The optimum condition would be to have a multiple of 2000 bananas at P1 and 1000 bananas at P2 since the lousy creature can carry only 1000kg at a time

0 to P1: 2 round trips and 1 one-way trip leaving us with 2000 bananas at P1. i.e. 5*P1=1000 => P1=200 Km

P1 to P2: 1 round trip and 1 one-way trip leaving us with 1000 bananas at P2.
i.e. 3*(P2-P1) = 1000 => P2-P1 = 1000/3 => P2 = 1600/3

At P2 we have 1000 bananas and (3000-1600)/3 = 1400/3 km to go

So at the 1000Km mark we are left with 1600/3 bananas.

I still say kill and cook the elephant and have a feast.
This is similar to my method (before I found out that miles backward count!)

The elephant will take 1000 widgets to P2 (using 333), drop 334, and take 333 back to P1 (using all 333). Then it will take the remaining 1000 to P2, using 333 more, pick up 333 of the 334 left at P2, and carry all 1000 the 467km to the end, leaving him with 533 left.

My answer (in light of the clarified usage rules) is 533.

Edited b/c I am lame and can't do '1600/3'

#### outofloop

##### Member
533

1st trip: (going)take 1000: drop 4 eat 1 at each km - reaches 200km (with 4 balls at each of the first 200km)
1st trip: (returning) eat 200 - 600 left on ground (with 3 balls at each of the first 200km)
2nd trip: (going)take 1000: eat 200 from ground for the first 200 km then drop 2 eat 1 at each km for the next 333 km
2nd trip (returning) eat 533 on the ground ( 533 left at each km now)
3rd trip: take 1000: eat 533 on ground then 467 from the 1000 carrying
reach the city with 533

#### OdiN

##### Banned
Originally posted by: TecHNooB
Originally posted by: OdiN
Originally posted by: TecHNooB
Originally posted by: OdiN
Originally posted by: TecHNooB
Originally posted by: OdiN
Originally posted by: TecHNooB
No right answers yet, keep trying!
My answer is correct. Others probably as well.

If you want to post a real problem, go ahead. But there are too many holes in your existing one.
Tell me about it, ill clear it up.
You aren't specifying if he has to eat during the walk. You never said you can or cannot drop stuff off and pick them up later. You don't take large grues into account.
It was meant to be semi hazy You're supposed to figure that out yourself. It starts out more like a riddle and ends in a math question. Grue?
I'll just be hazy when describing something to an engineer so that when the bridge is built the traffic on it collapses and hundreds of people die.

Call it a riddle if you want to be hazy. Not a math problem.
What kind of engineer are you?
Database.

But I wasn't talking about me.

##### Diamond Member
Originally posted by: OdiN
Originally posted by: TecHNooB
Originally posted by: OdiN
Originally posted by: TecHNooB
Originally posted by: OdiN
Originally posted by: TecHNooB
No right answers yet, keep trying!
My answer is correct. Others probably as well.

If you want to post a real problem, go ahead. But there are too many holes in your existing one.
Tell me about it, ill clear it up.
You aren't specifying if he has to eat during the walk. You never said you can or cannot drop stuff off and pick them up later. You don't take large grues into account.
It was meant to be semi hazy You're supposed to figure that out yourself. It starts out more like a riddle and ends in a math question. Grue?
I'll just be hazy when describing something to an engineer so that when the bridge is built the traffic on it collapses and hundreds of people die.

Call it a riddle if you want to be hazy. Not a math problem.
Yep stuff like this pisses me off, it was clear from the start it was a trick question... If were just gonna assume things, the answer is easy - he throws 2000 balls to the town and uses the remaining 1000 to travel

... Stupid

#### OdiN

##### Banned
Originally posted by: OdiN
Originally posted by: TecHNooB
Originally posted by: OdiN
Originally posted by: TecHNooB
Originally posted by: OdiN
Originally posted by: TecHNooB
No right answers yet, keep trying!
My answer is correct. Others probably as well.

If you want to post a real problem, go ahead. But there are too many holes in your existing one.
Tell me about it, ill clear it up.
You aren't specifying if he has to eat during the walk. You never said you can or cannot drop stuff off and pick them up later. You don't take large grues into account.
It was meant to be semi hazy You're supposed to figure that out yourself. It starts out more like a riddle and ends in a math question. Grue?
I'll just be hazy when describing something to an engineer so that when the bridge is built the traffic on it collapses and hundreds of people die.

Call it a riddle if you want to be hazy. Not a math problem.
Yep stuff like this pisses me off, it was clear from the start it was a trick question... If were just gonna assume things, the answer is easy - he throws 2000 balls to the town and uses the remaining 1000 to travel

... Stupid
No - he uses the trebuchet readily available at the first town to fire all 3000 balls to the next town, and then flings himself there afterwards, using no balls at all.

#### Lifted

##### Diamond Member

Yep stuff like this pisses me off, it was clear from the start it was a trick question... If were just gonna assume things, the answer is easy - he throws 2000 balls to the town and uses the remaining 1000 to travel

... Stupid
Just modify it so that he throws the ballz as far as possible, walks to them and throws them again, repeating until he gets 1 KM, then he eats one. Ends up with 2000 balls by the time he reaches the town.

#### OdiN

##### Banned
Originally posted by: Lifted

Yep stuff like this pisses me off, it was clear from the start it was a trick question... If were just gonna assume things, the answer is easy - he throws 2000 balls to the town and uses the remaining 1000 to travel

... Stupid
Just modify it so that he throws the ballz as far as possible, walks to them and throws them again, repeating until he gets 1 KM, then he eats one. Ends up with 2000 balls by the time he reaches the town.
Yup that would work. Just load up 1000 balls (or 999 if he can't hold that one extra) and then just throw one by one as you go.

#### SSSnail

##### Lifer
Sorry, can't compute.

First off, is the elephant unionized? Secondly, you said what's the greatest value of stuffs he can take to the next town, well that depends a lot on whether the elephant works 8 hours a day, and when it retires. I haven't even asked you about towing capacity of such elephant.

Cannot compute lah.