Binomial
Geometric
Random Variables
According to Russo
Combining Random Variables
100

Name the four conditions for a Binomial Distribution.

Fixed number of trials

Independent Trials

Equal Probability of Success

Each trial can result in a success or failure


100

A geometric distribution focuses on the ____________ success.

First

100
Let X = the height of a randomly selected student from our class.   What type of random variable is X?

Continuous

100

Greatest quarterback of all time.

Eli Manning

100

Let 

sigmax = 3 and sigmay = 5

sigma (x+y)

Need to know they are independent

200

HMHS is a population of 800 students of which the percent of students who ate breakfast is fixed.   You're choosing a sample and counting the number of students ate breakfast today.   How large of a sample can you take and still treat this problem as Binomial?

80

200

A scratch off is 20% likely to be a winner of some sort.  You decide to purchase tickets until you win.  What is the probability that you only purchase two tickets?

.16

200

You are playing a lottery, which costs $2, in which the expected winning on each ticket is .89$.   Explain what this means in regards to how much you lose when you play.

Over many tickets, the player would lose around $1.11 on each ticket.
200

Greatest High School Sport

Cross Country

200

Suppose we know Reid runs normally with a mean of 4.58 minutes in a 1600 and a standard deviation of .42 minutes.  

Suppose we know Ben runs normally with a mean of 5.02 minutes in a 1600 and a standard deviation of .28 minutes.    Find the average combined time if both boys ran the 1600.

9.60 minutes

300

Blaise is 68% likely to make free throws at Intermural Basketball.  In a sample of 15 shots, what is the probability that he makes exactly 9?  Must show work with substitutions.

15C9 (.68)^9(.32)^6

.1671

300

A scratch off is 20% likely to be a winner of some sort.  How many tickets can you expect to purchase before you win?

5

300

Let X by the amount of money won on a lotter ticket.   

Find P(X = $10)

.058

300

Greatest baseball player of all time

Ronald Acuna

300

Suppose we know Reid runs normally with a mean of 4.58 minutes in a 1600 and a standard deviation of .42 minutes.  

Suppose we know Ben runs normally with a mean of 5.02 minutes in a 1600 and a standard deviation of .28 minutes.  If the two were to run independently of each other, find the standard deviation of Reid's time + Ben's time.

.505 minutes

400

Blaise is 68% likely to make free throws at Intermural Basketball.  In a sample of 15 shots, what is the probability that he makes more than 9 shots?  Must show work with substitutions.

15C10 (.68)^10(.32)^5+...+.68^15

.6607

400

A scratch off is 20% likely to be a winner of some sort.  You purchase tickets until you win.  What is the probability that you purchase less than 5 tickets?  Show work and answer

.2+...+.8^3(.2)

.5904

400

Find and interpret the expected value of X, the amount won on a single lottery ticket.

Over many ticket purchases, the ticket will pay about $2.46 (minus the cost of the ticket)


400

Statisticians never get

Lucky

400

Suppose we know Reid runs normally with a mean of 4.58 minutes in a 1600 and a standard deviation of .42 minutes.  

Suppose we know Ben runs normally with a mean of 5.02 minutes in a 1600 and a standard deviation of .28 minutes.  

The two boys runs a 2 man relay in which each runs a 1600, independently of the other.  Find the probability that their total time is slower than 10 minutes.  Show all work for credit.

.2148

500

Blaise is 68% likely to make free throws at Intermural Basketball.  In a sample of 15 shots, what is the probability that he makes between 6 and 9 shots inclusive?  Must show work with substitutions.

15C6(.68)^6(.32)^9+...+15C9(.68)^9(.32)^6

.3331

500

A scratch off is 20% likely to be a winner of some sort.  You decide to purchase tickets until you lose.  What is the probability that you purchase more than 5 tickets?  Show work and answer

1- (.8+...+.8(.2)^4)

.0003


500

Find, and interpret, the standard deviation of X, the amount won on a single purchase of a lottery ticket.

On average, over many ticket purchases, the winnings vary by about $44.70
500

Best poster on instagram

Coach Bennett

500

Suppose we know Reid runs normally with a mean of 4.58 minutes in a 1600 and a standard deviation of .42 minutes.  

Suppose we know Ben runs normally with a mean of 5.02 minutes in a 1600 and a standard deviation of .28 minutes.  

The two boys run a 1600, independently of the other.  Find the probability that Reid is faster than Ben.  Show work for credit

.8078