Random Variable Problems & Solutions

A standard deck of cards contains 52 cards. One card is selected from the deck. (a) Compute the probability of randomly selecting queen or nine . (b) Compute the probability of randomly selecting queen or nine or king. (c) Compute the probability of randomly selecting nine or diamond.

Sara Faghani2022-03-25

Dottie’s Tax Service specializes in federal tax returns for professional clients, such as physicians, dentists, accountants, and lawyers. A recent audit by the IRS of the returns she prepared indicated that an error was made on 7 percent of the returns she prepared last year. Assuming this rate continues into this year and she prepares 80 returns, what is the probability that she makes errors on: a. More than six returns? b. At least six returns? c. Exactly six returns?

Assume a binomial probability distribution with n = 50 and p =0.25. Compute the following: a. The mean and standard deviation of the random variable. b. The probability that X is 15 or more. c. The probability that X is 10 or less.

If 16 customers on average stop by Dunkin' Donuts per hour. Then what is the probability that 5 customers will stop by in half an hour? * Pick the nearest number to your answer.a.065b. 0.0916c. .05d. 0.5

If the joint probability density function of two continuous random variables X and Y isgiven by f(x; y) = 2, 0 < y < 3x, 0 < x < 1;find,(a) f(y/x),(b) E(Y/x), (c) Var(Y/x).

Find the density of random vairable Z=X+Y, whare X and Y two independent uniform random vairableS over (-1, 1)?

Suppose that the height, in inches, of a 20-year-old man is a normal random variable
with parameters μ = 175 and σ = 10.
There are ten 20-year-old men in the class. What's the probability that more than 8
of them are over 185cm?

2–6. Resolve F2 Into Components Along The U And V Axes, And Determine The Magnitudes Of These Components. F2 = 150 N V 30° 30° 45° F1 = 200 N

Randy Dean 2022-02-11

I need to figure out how or where to find the standard deviation and mean for this problem Given that z is a standard normal random variable, compute the following probabilities.
a. P(z≤−1.0)
b. P(z≥−1)
c. P(z≥−1.5)
d. P(−2.5≤z)
e. P(−3

Addison Gross 2022-01-30

What are the mean and standard deviation of a probability density function given by $P r (X = k) = \frac{12^{k} e^{- 12}}{k!}$ for $k \in {0, 1, 2. . . \infty}$ ?

meteraiqn 2022-01-30

Can a sample have a standard deviation of zero?

Dayton Burnett 2022-01-30

What is the value of x if 100,120,103,133,109,x have a mean of 110?

siutulysr5 2022-01-30

Which has a better relative position: a score of 75 on stats test with a mean of 60 and a standard deviation of 10 or a score of 36 on an accounting test with a mean of 30 and a variance of 16?

Alex Cervantes 2022-01-30

A distribution has a mean of 10400.93 and a standard deviation of 5112.49. What is one standard deviation below the mean?

Adrian Cervantes 2022-01-30

What are the mean and standard deviation of a probability density function given by $P r (X = k) = \frac{24^{k} e^{- 24}}{k!}$ for $k \in {0, 1, 2. . . \infty}$ ?

segnverd3a 2022-01-30

What are the mean and standard deviation of a probability density function given by $P r (X = k) = \frac{9^{k} e^{- 9}}{k!}$ for $k \in {0, 1, 2. . . \infty}$ ?

Emmy Combs 2022-01-30

What are the mean and standard deviation of a probability density function given by $P r (X = k) = \frac{14^{k} e^{- 14}}{k!}$ for $k \in {0, 1, 2. . . \infty}$ ?

GrareeCowui 2022-01-30

What does a small standard deviation signify? What does a large standard deviation signify?

When you have an equation that deals with random variables, always start with an explanation related to some random variable examples. It is what the majority of skilled engineers do because it is the only way how one can avoid mistakes when working with statistical data. Even though this part of statistics and probability may seem overly complex, approach every random variable equation through the lens of probability as you seek answers to your questions. Compare provided solutions, see similarities, and you will achieve the most efficient solutions.

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