What Is the Probability of Getting a Lift Within an Hour?

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The discussion centers on calculating the probability of getting a lift within an hour, given that cars pass at an average rate of one per minute and each car has a one percent chance of stopping. The Poisson distribution is identified as relevant, with λ set to 60 for the hour. Participants suggest calculating the probability of not getting a ride and then subtracting that from one. There is also mention of the need to consider both the number of cars passing and the likelihood of each car stopping. Understanding the exponential series is suggested as a potential method for solving the problem.
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Cars pass at randoms times at an average rate of one a minute. The chance of a car stopping to give you a lift is one percent. What is the probability you will have got a lift within one hour?

This has pretty much stumped me. I know λ=60 as expecting 60 cars an hour for the poisson distribution but there's a binomial aspect to this as well because of each car either giving you a lift or not giving you a lift
 
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It's probably easiest to calculate the probability you don't get a ride and then subtract that from 1.
 
I agree! But how?
 
What's the probability that exactly n cars pass in an hour?
 
If N is the number of cars passing in time t, the event E = {no ride in time t} consists of {N=0} or {N=1 & no ride} or {N=2 & no ride} or ... . Are you familiar with the exponential series? If not, see http://en.wikipedia.org/wiki/Exponential_function .

RGV
 
I tried to combine those 2 formulas but it didn't work. I tried using another case where there are 2 red balls and 2 blue balls only so when combining the formula I got ##\frac{(4-1)!}{2!2!}=\frac{3}{2}## which does not make sense. Is there any formula to calculate cyclic permutation of identical objects or I have to do it by listing all the possibilities? Thanks
Since ##px^9+q## is the factor, then ##x^9=\frac{-q}{p}## will be one of the roots. Let ##f(x)=27x^{18}+bx^9+70##, then: $$27\left(\frac{-q}{p}\right)^2+b\left(\frac{-q}{p}\right)+70=0$$ $$b=27 \frac{q}{p}+70 \frac{p}{q}$$ $$b=\frac{27q^2+70p^2}{pq}$$ From this expression, it looks like there is no greatest value of ##b## because increasing the value of ##p## and ##q## will also increase the value of ##b##. How to find the greatest value of ##b##? Thanks

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