What is the expected number of mutual friends Sara and Tom have? Sara and Tom have just met, and wonder whether they have mutual friends.Each has 50 friends, out of 1,000 other people who live in their town. They think thatit's unlikely that they have a friend in common, saying "each of us is only friends with5% of the people here, so it would be very unlikely that our two 5%'s overlap."Assume that Sara's 50 friends are a random sample of the 1000 people (i.e., equally likelyto be any 50 of the 1000), and similarly for Tom. Also assume that knowing who Sara'sfriends are gives no information about who Tom's friends are.What is the expected number of mutual friends Sara and Tom have?Hint: You may consider creating an indicator random variable for each person in theirtown.

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Description: What is the expected number of mutual friends Sara and Tom have? Sara and Tom have just met, and wonder whether they have mutual friends.Each has 50 friends, out of 1,000 other people who live in their town. They think thatit's unlikely that they hav

Sara and tom each have 50 mutual friends out of 1000

Answered: e a friend in common, t would be very…

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e a friend in common, t would be very unlik nds are a random samp zand similarly for Tom

MATLAB: An Introduction with Applications

6th Edition

ISBN:9781119256830

Author:Amos Gilat

Publisher:Amos Gilat

Chapter1: Starting With Matlab

Section: Chapter Questions

Problem 1P

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Concept explainers

Contingency Table

A contingency table can be defined as the visual representation of the relationship between two or more categorical variables that can be evaluated and registered. It is a categorical version of the scatterplot, which is used to investigate the linear relationship between two variables. A contingency table is indeed a type of frequency distribution table that displays two variables at the same time.

Binomial Distribution

Binomial is an algebraic expression of the sum or the difference of two terms. Before knowing about binomial distribution, we must know about the binomial theorem.

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What is the expected number of mutual friends Sara and Tom have?

Sara and Tom have just met, and wonder whether they have mutual friends.
Each has 50 friends, out of 1,000 other people who live in their town. They think that
it's unlikely that they have a friend in common, saying "each of us is only friends with
5% of the people here, so it would be very unlikely that our two 5%'s overlap."
Assume that Sara's 50 friends are a random sample of the 1000 people (i.e., equally likely
to be any 50 of the 1000), and similarly for Tom. Also assume that knowing who Sara's
friends are gives no information about who Tom's friends are.
What is the expected number of mutual friends Sara and Tom have?
Hint: You may consider creating an indicator random variable for each person in their
town.

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