Chapter 4

Discrete vs Continuous

100

What is the difference between discrete and continuous variables?

What is discrete=countable, continuous= not countable

200

The speed of a race car in mph.

What is continuous.

300

The number of math majors at USC.

What is discrete.

400

The number of people that play the NH Lottery each day.

What is discrete.

500

The number of cups of coffee that SpeedyUrchin drinks each day.

What is continuous or discrete.

Probability Distributions

100

The probabilities in a probability distribution should add up to what?

What is one.

200

Is the following a probability distribution? x: 1 2 3 4 p(x): .23 .32 .45 .07

What is no because the probabilities do not add up to 1.

300

A box contains 3 markers, 2 pens, 1 crayon, and 1 sharpie. Define the variable and construct a probability distribution.

Let x be the kind of writing instrument x: marker pens crayon sharpie P(x): 3/7 2/7 1/7 1/7

400

Below is a probability distribution for the number of math failures of BC students. x: 0 1 2 3 4 P(x): .41 .38 .08 .02 Find the missing probability and find P(x <3).

What is P(2)= .11 P(x<3)= .90

500

Using your graphing calculator, find the mean for the following probability distribution: x: 0 1 2 3 4 5 6 P(x): .04 .26 .36 .20 .08 .04 .02

Mean  = sum of all x *p(x)

What is mean=2.22 

Binomial Distributions

100

Binomial or not? Flipping a coin

NO

200

Binomial or not? Counting the number of purple frogs on a tree that contains 100 frogs. The probability of a frog being purple is 2%

Yes

300

A packet of vegetable seeds has a germination rate of 96%. What is the probability that exactly 10 of 12 seeds planted will sprout?

What is .0702

400

What are the 4 conditions for using a binomial distribution?

What is 1. success/failure 2. finite # of trials 3. events are independent 4. probability of success has to be constant

500

A manufacturer of halogen bulbs knows that 3% of the production of their 100 W bulbs will be defective. What is the probability of choosing 5 defective lightbulbs from a 144 bulb box if the lightbulbs are not replaced after picking?

What is cannot use binomial distribution to solve. It is not independent.

Other Distributions

100

Describe the difference between a binomial distribution and a poisson distribution.

Binomial uses a probability/percentage whereas a poisson uses an expected value (average)

200

Describe a geometric distribution?

Answers may vary/refer to teacher

300

What type of distribution? Picking a red marble out of a bag of various marbles on your 6th try with replacement. 

Geometric