Discrete and Continuous Random Variables
Binomial Random Variables
Expected Value and Standard Deviation
100
The probability distribution of a discrete random variable must have outcome probabilities that are between ___ and ___ and that add up to ___.
What is 0 and 1 and 1.
100
Name all 4 conditions that a binomial random variable must meet and briefly explain each one.
What is BINS (binary, independent, number of trials, success)
100

What is the Expected Value Formula for a Discrete Random Variable?

x1p1 + x2px +x3p3 +....

sum_(i=0)^N x i p i

200
Is this an example of a discrete or continuous random variable: Record the number of red cars, x, that pass through an intersection between 5 and 6 pm on a randomly selected day.
What is discrete random variable.
200
What is the binomial probability formula? and What does k represent?
What is P(x=k)=(binomial coefficient) p^k(1-p)^(n-k) k is the number of successes.
200

What is the Standard Deviation Formula for a Discrete Random Variable? 

See White Board.

300
Is this a continuous or discrete random variable? Record the average high temperature, y, in Nashville on a randomly selected day.
What is continuous random variable.
300
What is the binomial coefficient and how is it found?
What is the number of ways of arranging k successes among n observations nCr or n!/k!(n-k)!
300

What is the Expected Value AND Standard Deviation Formula of a Binomial Random Variable.

Expected Value = (n)(p)

Standard Deviation = 

sqrt((n)(p)(1-p)

400
Find the mean (or expected value of this random variable). Outcome #1: -$1 Probability: 20/38 Outcome #2: $1 Probability: 18/38
What is -$0.05
400
A certain flower seed has an 85% change of growing. Judy gets a packet with 20 randomly selected seeds and plants them. Let x = the number of seeds that grow. Is this binomial? Explain why or why not?
What is Binomial-yes
400

Below is Probability Distribution of the number of the number of siblings of Mr.A's 5th period. What is the Expected Value of (Expected number of) the siblings? Bonus for Finding Standard Deviation. 

See the Board

500
The length of a human pregnancy follows a Normal distribution with mean 266 days and standard deviation 16 days. Choose a pregnant woman at random. Let x = the length of her pregnancy. Find the value "c" such that P(x>c) = 0.20.
What is 279.47
500
A certain flower seed has an 85% change of growing. Judy gets a packet with 20 randomly selected seeds and plants them. Let x = the number of seeds that grow. Find the probability that exactly 17 seeds grow.
What is 0.2428
500

A multiple choice test has 5 options and only one answer is the correct option. If Mr. A gives a 30 question test, what is the Expected Value of Correct answers you would get by just guessing? What would the Standard Deviation of the test be?

E(x) = (30)(1/5) = 6 questions correct

SD = 

sqrt((30)(1/5)(4/5)) = 2.19

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