working out % chance?

[machine]

I havent done GCSE maths for years but am good at maths but for some reason cant work this out. assuming there is a 1 in 22 chance of getting in the deal or no deal chair, how do i work out what the odds are of being picked after 1 show,2 shows,etc,etc also how do you combine odds of something happening acummualtively for example 50% 20% 9% 14% is it 0.5x0.2x0.09x0.14=0.126%? chance of happening

sorry for being newbish

cheers guys

[filsteal]

I'm not sure if I quite understand what you're asking, but I'll try to give an answer.

Let's say something has a 10% chance of happening on the 1st try. If it fails on the first try, then it has a 15% chance of happening on the 2nd try. If it fails again, then it has a 19% chance on the 3rd try.

Suppose you want the probability that it happens on either the first, second, or third try. That's equal to 100% MINUS the probability that it FAILS on all three tries. So

1 - (.9 x .85 x .81)

is your answer, if I'm understanding your question right.

[machine]

assuming a 1 in 22 chance what is the chance of this event not happening after 5 times? 1 in 22 every time, not 1 in 21, 1 in 20 etc

[igetbadbeat]

[ QUOTE ]
assuming a 1 in 22 chance what is the chance of this event not happening after 5 times? 1 in 22 every time, not 1 in 21, 1 in 20 etc

[/ QUOTE ]

Your original wording is faulty. If you miss it the first time, your chances don't go up the 2nd time.

From the beginning when you have 3 chances, the odds of you not getting picked are 1-(1/22+1/22+1/22) or rather 19/22 is the odds you don't get it.

If you don't get picked the first time, your odds are 20/22 of not getting picked

and if you don't get picked the first two times, your odds are 21/22 not tog et picked @ that point.

[igetbadbeat]

for 5X, your odds are 17/22 to NOT MAKE IT.

[Elandriel]

How does this work when it comes to 2/22 - 1/22 - ???

[machine]

its easy to work out your chance of making it 5 times in a row but not being picked 5 in a row? your theory is surely flawed as mentioned above, what happens say after 40 times?

[jimmyfingers]

when you say picked after 1 show, 2 shows, etc., do you mean picked during any of the previous shows or picked on that specific show?

probability(picked before show X) = 1 - prob(not picked for X shows) = 1 - (21/22)^X

[JustBeginning]

If the chances of being picked in each show is 1/22 (if I'm thinking of the right show it is as they replensih the numbers each time),
Chances of being picked in first show are 1/22
Chances of being picked in second show are 1/22
etc.
Chances of being being picked by first show are (1-21/22) = 2/22 = 4.5%
Chances of being being picked by second show are 1-(21/22 *21/22) = 8.9%
Chances of being being picked by third show are 1-(21/22 *21/22*21/22) = 13.1%
etc.
Or to formalise it 1-(21/22)^X where x is the number of shows.
If the number of people left that are up to qualify goes down then it's slightly different.

[oldbookguy]

First, there is more information needed.
First show you state 1/22 so there are 22 people to choose from.
For show 2 selection, is the number of people reduced by 1, leaving only 21 people, then third show, reduced again by 1, leaving 20 people or is the field of selectees reset to 22 each time?

Additionally, is being selected based on critria you and the others may use to exploite during the second chance (important if selectees are reset each time to 22) or is more like a lottery or bingo game, a number is randomly drawn to select the Deal or No Deal chair person?