Exam #3 - Chapter 5/6

Assume that when adults with smartphones are randomly​ selected, 33​% use them in meetings or classes. If 7 adult smartphone users are randomly​ selected, find the probability that exactly 3 of them use their smartphones in meetings or classes.

P(Exactly 3) = 0.2535

Assume that when adults with smartphones are randomly​ selected, 32​% use them in meetings or classes. If 15 adult smartphone users are randomly​ selected, find the probability that exactly 8 of them use their smartphones in meetings or classes.

P(Exactly 8) = 0.0476

N=12, P=0.45, X<4 A binomial probability experiment is conducted with the given parameters. Use technology to find the probability of x successes in the n independent trials of the experiment.

P(X<4) = 0.1345

What are the requirements for a binomial probability distribution?

1) Fixed number of trials 2) Independent 3) Two outcomes 4) Probabilities remain constant for each trial

What are the requirements for a probability distribution?

1) Valid 2) Total = 1

What is a normal distribution?

A continuous random variable has a distribution w/ a graph that is a symmetric and bell shaped

The overhead reach distances of adult females are normally distributed with a mean of 204 cm and a standard deviation of 8.5 cm. A. Find the probability that an individual distance is greater than 216 cm. B. Find the probability that the mean for 23 randomly selected distances is greater than 202 cm.

A. 0.0793 B. 0.8708

Assume that females have pulse rates that are normally distributed with a mean of mu equals 77 beats per minute and a standard deviation of sigma equals 12.5 beats per minute. A. If 1 adult female is randomly​ selected, find the probability that her pulse rate is between 69 beats per minute and 85 beats per minute. B. If 16 adult females are randomly​ selected, find the probability that they have pulse rates with a mean between 69 beats per minute and 85 beats per minute.

A. 0.4778 B. 0.9896

Assume that females have pulse rates that are normally distributed with a mean of mu equals 77.0 beats per minute and a standard deviation of sigma equals 12.0 beats per minute. A. If 1 adult female is randomly​ selected, find the probability that her pulse rate is less than 83 beats per minute. B. If 9 adult females are randomly​ selected, find the probability that they have pulse rates with a mean less than 83 beats per minute.

A. 0.6915 B. 0.9332

The probability of a girl is 0.5. Assume that the groups consist of 56 couples Find the: A. Mean B. Standard Deviation C. Minimum Value D. Maximum Value

A. 28 B. 3.7 C. 20.6 D. 35.4

There is a 0.75 probability that a pea has green pods. Assume that the offspring peas are randomly selected in groups of 52. Find the: A. Mean B. Standard Deviation C. Minimum Value D. Maximum Value

A. 39 B. 3.1 C. 32.8 D. 45.2

Is the exact time it takes to evaluate 27 + 72 a discrete random variable, a continuous random variable, or not a random variable?

It is a continuous random variable

The amount of rain in city A during July a discrete random variable, a continuous random variable, or not a random variable?

It is a continuous random variable

Is the number if statistics students now reading a book a discrete random variable, a continuous random variable, or not a random variable?

It is a discrete random variable

Is the number of people with blood type A in a random sample of 17 people a discrete random variable, a continuous random variable, or not a random variable?

It is a discrete random variable

Is the eye color of people on commercial aircraft flights a discrete random variable, a continuous random variable, or not a random variable?

It is not a random variable

What requirements are necessary for a normal probability distribution to be a standard normal probability​ distribution?

Mean = 0 Standard Deviation = 1

x P(x) 0 0.001 1 0.009 2 0.028 3 0.062 Does the table show a probability distribution?

No

Treating 150 bald men with a special shampoo and recording how they say their scalp feels? Is the given probability a binomial distribution?

No, because there are more than two possible outcomes

N=4, P=0.80, X=3 Use a binomial probability table to find the probability that the number of successes x is exactly 3.

P(3) = 0.410

Assume that when adults with smartphones are randomly​ selected, 62​% use them in meetings or classes. If 12 adult smartphone users are randomly​ selected, find the probability that at least 9 of them use their smartphones in meetings or classes.

P(At least 9) = 0.2704

Continuity Correction: Probability of fewer than 9 passengers who do not show up for a flight

The left of 8.5

An experimental drug is administered to 40 randomly selected​ individuals, with the number of individuals responding favorably recorded Is the given probability a binomial distribution?

Yes

x P(x) 0 0.031 1 0.149 2 0.320 3 0.320 4 0.149 5 0.031 Does the table show a probability distribution?

Yes

When can you use the normal distribution to approximate the binomial distribution?

You have to use the formulas, NxP and NxQ. If both of answers are larger than 5, then you use the 5-6 steps to find the answer.