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If i choose 20 cell phone numbers randomly in a population of 37 100 000 cell phone subscribers, how large is the probability that at least two of them during two days in a row (a 48 hour period) will make a call to another person in this group of 20? The actual case involve a call and then an immeditate call back, which should mean that the two subscribers know each other: So the question can maybe be reformulated: How large is the probability in a population ot 37 100 000 that two persons in a random sample of 20 drawn from the 37 100 000 know each other?



Is this enough information to answer the question?

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The fact that the random sample has a size of 20 and was picked from 37,100,000 people allows us to find out that the probability that two people in that sample know each other is 0.0036.

What is the probability of two people knowing each other?

To solve this, we would need to use the binomial probability formula because the likelihood that two people from the sample of 20 know each other will only be determined by a system of trials.

The probability that two people in a sample of 20, picked from a population of 37,100,000 knowing each other is:

= (20! / 2!(20-2)!) x (0.5²) x ((1-0.5)²⁰⁻²)

Solving gives:

= (20! / 2!(20-2)!) x (0.5²) x ((1-0.5)²⁰⁻²)

= (20! / 2!(18)!) x 0.0625 x 0.328

= 0.0036

In conclusion, the probability that two people know each other from a sample of 20 people is 0.0036.

Find out more on binomial probability at https://brainly.com/question/15718689

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