Fifty Cents
A drink machine has three options Coke, Pepsi and Random. Each drink is fifty cents. A friend tells you that the machine is faulty and that the buttons are never correct.
How much money would you need to spend to know which buttons deliver which drinks?
How much money would you need to spend to know which buttons deliver which drinks?
Labels: logic, mathemagic
posted by Rajesh Lal at
10:55 PM
27 Comments:
50c.
Select random, this will give you either a coke or pepsi.
If Coke:
Random = Coke
Pepsi = Random
Coke = Pepsi
If Pepsi:
Random = Pepsi
Coke = Random
Pepsi = coke
2 dollars
50 cent 2 times on 2 buttons
more than $2
50c on all three= $1.50
and then another 50c until one of the two that came out the same changes that one is random.
what difference does it make? ... coke and pepsi are the friking same, for gods sake. i just think that person is fussy...
plus, if the machine is faulty i would go somewhere else.
If the buttons are NEVER correct, then you would NEVER know.
No the first guy is correct, because if they are incorrect, you know that whichever comes out therandom is what it always spits out and then then whichever label matches the one came out its the opposite of what is says I.E. Coke would be pepsi or pepsi would be coke then the one that hasn't been chosen yet is random
$0.50
The first choice will be wrong. Take the one you actually got and you know the other two will be wrong as well...to the other one left.
If one button is RANDOM, then you would never be sure of what it would give. Random means that it maybe either one. It might even give nothing. (I have found that button quite a few times).
If it is random, then you can't tell what the next one will be. If you could, then it would not be random.
If one button is RANDOM, then you would never be sure of what it would give. Random means that it maybe either one. It might even give nothing. (I have found that button quite a few times).
If it is random, then you can't tell what the next one will be. If you could, then it would not be random.
pepsi and coke taste the same. big deal. If the machine is broken go to another one.
You would need $1.50 since there are 3 buttons each with one selection and each selection costs c50!
Pearl says; You would need $1.50 cause there are 3 choices, Pepsi, Coke and random, each choice costs C50 so the answer is $1.50
$1.50
this is a dumb question just dont hit the random button
Per first poster:
If _every_ button is _always_ wrong, then 0.50 is enough: hit the button labeled 'random'; if it dispenses a Coke, then the button marked 'Pepsi' must dispense randomly and the one marked 'Coke' must dispense Pepsi. Otherwise, if the 'random' button gives a Pepsi, then the 'Coke' button is random and the 'Pepsi' button gives Coke.
wow you are all retarted the cents sign what you are using c for goes after the number (50c)
the first person was right. the reasoning for this has already been explained at least twice, so i guess i really don't need to say it again.
And for those of you who were talking about how coke and pepsi taste almoste exactly the same (with which i must agree), and how you would just go to another machine, that's really not the point of the question:) lol
you need at least $3 to test each button twice but you may need more to find the actual "random button" seeing that it will have to drop a drink different from the first trial. potentially you could spend millions of dollars (if you were stupid) if the random button just dropped the same soda each time.
Well just fifty cents because if, IF the random is coke then you would know that pepsi is random and coke is pepsi. If you didnt get that then THINK A LITTLE!!! :)
All u need is a one dollhair.cuz u can pick 2 buttons with that dollar n the thrid will become obvious!!!!!!!!!!!!
$1.50
Theoretically you could need up to an infinate amount of money to determine for sure which button will provide which selection.
You have 3 buttons
one button will give you a coke
one button will give you a pepsi
and the last button can either one because it is a random.
First, you put 50c for each of the buttons.
lets say that button A gave you a Pepsi, button B gave you a coke and button C gave you a coke.
From here, you can safely say that button A distributes Pepsi because B and C both gave out a coke which means one of them is the Coke and the other is random.
Now you place 50c for the buttons B and C. and you continue to do so until one of the buttons give you a pepsi.
You have an equal 50% chance you will get a pepsi or a coke for the random button, therefore it is possible but highly unlikely that both Button B and C will continue to distribute only Coke for eternity, assuming that the drink machine is refilled continuly.
The least possible amount of money you can spend on this is $2.00
first, 50c for each of the buttons which you can deduce that one of two buttons will be the random. and by chance you pay another 50c and happen to pick the random and it gives you the other drink than it gave you previously.
The chance of this scenario happening is 25%
The chance of the enternity scenario happening is 1 multiplied by 10 to the power of negative infinity
it never says that random is either coke or pepsi. it could be any flavor. so you would need $1. 50 cents to check the first two buttons and the third is obviously whatever flavor is left.
just $1
Choose 1, then the button is either random, pepsi, and coke.
You either earn pepsi or coke.
Then if you earn the same as the last one, then the third button must be either pepsi or coke, depending on what you get on the first time.
1.50 for each type!
$1.00.
because you need 50 cents to figure out one of them,
then do the same again with another 50 cents,
then you'll know what other button would be the remaining drink.
What so many people are missing is that the question says the labels on the buttons are ALWAYS wrong. So the button labelled 'random' CANNOT actually be random. So if it is not really the random button, it must actually be EITHER the coke button OR the pepsi button. Once you have spent 50c on this button, you can work out what they all are.
David
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