Question

You are surveying people exiting from a polling booth and asking them if they voted independent. The probability (p) that a person voted independent is 20%. What is the probability that 15 people must be asked before you can find 5 people who voted independen

Answer 1

Explanation:

Let the distribution law followed is exponential law .

mean m = np where n = 15 , p = .2

m = 15 x .2 = 3

probability of 5 successes

=
`(e^(-m)m^r)/(r!)`

=
`(e^(-3)3^5)/(5!)`

= .1