@thenorfolkmafia
active 7 years, 1 month agoForum Replies Created
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Basically what I am saying is the first doors fixed 33.3% probability chance now alters when the third door is opened and the fixed chance of 33.3% of door 3 gets split between door 1 and 2 equally creating a 50/50.
To summarise then , you believe if someone is left with 2 doors with a car behind one, there is a better chance of getting the car by switching doors. Aside from the computer programme, can you offer a logical explanation as to why?
That is correct. The easiest way to explain this is that there is always a 100% probability of the car being behind a closed door. Which gives a probability of any of three doors having a ~33% chance of having the car if all doors are closed. This part I assume everyone agrees with. When the goat door is opened it’s probability of having a car is reduced to 0%, so the 33% it previously had must be transfered to one of the other doors, as there is still a 100% chance of there being a car behind one of them. The door the contestant originally chosen has a fixed chance at the time they selected it, so the probability must then be transfered to the only other unopened door. Giving it a ~66% chance of having the car.
I understand the logic of what you have written but can’t correlate it with the basic premise of there being two doors with an equal chance of the goat or car being behind either. I have an issue with the “fixed probability” chance of the original door which must surely like the second door now alter in probability. Just because the initial choice was 33.3 % , doesn’t mean that remains static after new information comes to light ie the opening of door 3 and the goat which logically must mean each door now has a 50/50 chance.
The first step is to establish the capacity of the bath when full, for this I will create a fictional unit known as bath units. Using the first tap as a reference, the flow rate is 1 bu/min. This gives the bath a capacity of 12 bu. The second tap is twice as fast, so has a flow rate of 2 bu/m. Next we must establish the flow rate of the drain. If it empties 12 units in 8 minuites then the flow rate must be 1.5 bu/m (12/8). Turning on both taps gives us antotal input flow of 3 bu/m and, and the output flow remains the same at 1.5 bu/m. Resulting in a net flow of 1.5 bu/m (3-1.5). So we know that the bath will fill eventually. To calculate the time we must divide the capacity of the bath by the net flow rate of the system (12/1.5). This gives the fill time of the bath to be 8 minutes. Edit: To clarify, a bath unit (bu) is defined as how much water is produced by the first tap in one minuite.
You have redeemed yourself drac from the goat shame.. I knew you had it in you
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Impressive answer drac, my answer is based on the “one tap system ” taking a mean measurement from both taps but of course the question states ” both taps are on” not that they are ” feeding into one ” so retract the 81 minutes in shame
To summarise then , you believe if someone is left with 2 doors with a car behind one, there is a better chance of getting the car by switching doors. Aside from the computer programme, can you offer a logical explanation as to why?
I thought you were brighter than this drac, what do you think is the answer to this question out of curiosity ?
Allow drac to answer this mister Q before giving the answer please
That’s mathematically impossible
Why do you say that? When the alternate door is offered, 98 of the 99 goat doors are removed from the selection. The original choice has 1/100 (1%) chance of being the car, therefore the one remaining door must have a 99/100 (99%) chance of being the car.
Drac you have a good brain , for love of God use it. There aren’t “100 doors” there are 3 doors rendering your analysis of these odds and computer programme unfit for purpose. Even using your example, the summary of the odds is flawed as using your example, one door is removed from 100 meaning the original choice has a 1 chance in 99 doors of being the car which is not 1%. In addition to that you state ” 98 of the goat doors were removed from the 99″ which was not the question but pursuing this line , that means switching doors would not give you a ” 99%” chance of being a car . Re read what I have written and answer sensibly instead of going on about 100 doors.
This reminds me of my sat nav a few years back, I put in southampton and it was guiding me to Gatwick for flights to south korea
You have stated ..
If you run the simulation with 100 doors instead, staying with the initial door gives ~1% chance of winning, switiching doors gives a ~99% chance of winning.
That’s mathematically impossible
It depends on the university as some polytechnics masquerading as universities offering a degree in ” media studies ” have an entry standard so low that practically writing your own name correctly would enable you to enroll.
A quick search shows that Cambridge offers a masters in ‘film studies’, this isn’t something that is limited only to ex-polytechnics. I did my bachelors degree with Open University, which in practice doesn’t have any entry requirements at all. It was still a fairly comprehnsive and challenging course however.
The entry level to cambridge is a minimum of 3 A *s , whilst academic qualifications aren’t an overall guide to intelligence they can’t be attained by someone without some intellect. The universities offering entry level requirements of Ds etc are the places that aren’t fit for purpose
