A random variable X is normally distributed with ì = 60. Convert the value of X to a z-score, if the standard deviation is as given. X = 60; ó = 7 A) 7 B) 1 C) 60/70 D) 0

14,506 results
1. Probability

Sophia is vacationing in Monte Carlo. On any given night, she takes X dollars to the casino and returns with Y dollars. The random variable X has the PDF shown in the figure. Conditional on X=x , the continuous random variable Y is uniformly distributed

2. probability

Sophia is vacationing in Monte Carlo. On any given night, she takes X dollars to the casino and returns with Y dollars. The random variable X has the PDF shown in the figure. Conditional on X=x , the continuous random variable Y is uniformly distributed

3. Probability

For each of the following statements, determine whether it is true (meaning, always true) or false (meaning, not always true). Here, we assume all random variables are discrete, and that all expectations are well-defined and finite. Let X and Y be two

4. probability

Let K be a discrete random variable with PMF pK(k)=⎧⎩⎨⎪⎪1/3,2/3,0if k=1,if k=2,otherwise. Conditional on K=1 or 2, random variable Y is exponentially distributed with parameter 1 or 1/2, respectively. Using Bayes' rule, find the conditional PMF

5. probability

Determine whether each of the following statement is true (i.e., always true) or false (i.e., not always true). 1. Let X be a random variable that takes values between 0 and c only, for some c≥0, so that P(0≤X≤c)=1. Then, var(X)≤c2/4. TRUE 2. X and

6. Statistics

Let X be a random variable that takes integer values, with PMF pX(x) . Let Y be another integer-valued random variable and let y be a number. a) Is pX(y) a random variable or a number? b) Is pX(Y) a random variable or a number?

7. Probability

Question:A fair coin is flipped independently until the first Heads is observed. Let the random variable K be the number of tosses until the first Heads is observed plus 1. For example, if we see TTTHTH, then K=5. For K=1,2,3...K, let Xk be a continuous

8. probability

A fair coin is flipped independently until the first Heads is observed. Let K be the number of Tails observed before the first Heads (note that K is a random variable). For k=0,1,2,…,K, let Xk be a continuous random variable that is uniform over the

9. Probability

1.Let 𝑋 and 𝑌 be two binomial random variables: a.If 𝑋 and 𝑌 are independent, then 𝑋+𝑌 is also a binomial random variable b.If 𝑋 and 𝑌 have the same parameters, 𝑛 and 𝑝 , then 𝑋+𝑌 is a binomial random variable c.If 𝑋

10. Math

Suppose a baseball player had 211 hits in a season. In the given probability distribution, the random variable X represents the number of hits the player obtained in the game. x P(x) 0 0.1879 1 0.4106 2 0.2157 3 0.1174 4 0.0624 5 0.0060 a.) Compute and

11. Probability

The random variable X is uniformly distributed over the interval [θ,2θ]. The parameter θ is unknown and is modeled as the value of a continuous random variable Θ, uniformly distributed between zero and one. Given an observation x of X, find the

12. statistics

the random variable x is known to be uniformly distributed between 70 and 90. the probability of x having a value between 80 to 95 is

13. Math

Background: a number, e.g. 2 , can be thought of as a trivial random variable that always takes the value 2 . Let x be a number. Let X be a random variable associated with some probabilistic experiment. a) Is it always true that X+x is a random variable?

14. Probability & Statistics

The random variable X has a standard normal distribution. Find the PDF of the random variable Y , where: 1. Y = 5X−7 . 2. Y = X2−2X . For y≥−1 ,

15. math

A fair coin is flipped independently until the first Heads is observed. Let the random variable K be the number of tosses until the first Heads is observed plus 1. For example, if we see TTTHTH, then K=5 . For k=1,2,…,K , let Xk be a continuous random

16. Statistics

A random variable is normally distributed with a mean of 50 and a standard deviation of 5. b. What is the probability that the random variable will assume a value between 45 and 55 (to 4 decimals)? c. What is the probability that the random variable will

17. Probability

For each of the following statements, state whether it is true (meaning, always true) or false (meaning, not always true): 1. Let X and Y be two binomial random variables. (a) If X and Y are independent, then X+Y is also a binomial random variable. (b) If

18. statistics

Let x be a continuous random variable that is normally distributed with a mean of 65 and a standard deviation of 15. Find the probability that x assumes a value less than 44.

19. probability

Let 𝑋 and 𝑌 be independent continuous random variables that are uniformly distributed on (0,1) . Let 𝐻=(𝑋+2)𝑌 . Find the probability 𝐏(ln𝐻≥𝑧) where 𝑧 is a given number that satisfies 𝑒^𝑧

20. Economic

The distance a car travels on a tank of gasoline is a random variable. a. What are the possible values of this random variable? b. Are the Values countable? Explain. c. Is there a finite number of values? Explain. d. Is there random variable discrete or

21. statistics

If X is a random variable which is normally distributed with a mean of 100, then P(X100) True or False?

22. Probability

Suppose a random variable X can take any value in the interval [−1,2] and a random variable Y can take any value in the interval [−2,3] . a) The random variable X−Y can take any value in an interval [a,b] . Find the values of a and b : a= b= b) Can

23. Probability

The random variable K is geometric with a parameter which is itself a uniform random variable Q on [0,1]. Find the value fQ|K(0.5|1) of the conditional PDF of Q, given that K=1. Hint: Use the result in the last segment.

24. Statistics

The Random Variable X is normally distributed with mean 560 and standard deviation 20. Find P(X

25. Statistics

X is a normally distributed random variable X with mean 15 and standard deviation 0.25. Find the values xL and xR of X that are symmetrically located with respect to the mean of X and satisfy P(xL < X < xR) = 0.80. (Hint. First solve the corresponding

26. STATISTICS

A random sample of stock prices per share (in dollars) is shown. Find the 90% confidence interval for the variance and standard deviation for the prices. Assume the variable is normally distributed.

27. Probability

Let X be a random variable that takes non-zero values in [1,∞), with a PDF of the form fX(x)=⎧⎩⎨cx3 if x≥1, 0,otherwise. Let U be a uniform random variable on [0,2]. Assume that X and U are independent. What is the value of the constant c? c=

28. Statistics

Let X denote an exponential random variable with unknown parameter λ>0 . Let Y=I(X>5) , the indicator that X is larger than 5 . Recall the definition of the indicator function here is I(X>5)={1ifX>50ifX≤5. We think of Y as a censored version of the

29. probability

A random experiment of tossing a die twice is performed. Random variable X on this sample space is defined to be the sum of two numbers turning up on the toss. Find the discrete probability distribution for the random variable X and compute the

30. Probability

Let N,X1,Y1,X2,Y2,… be independent random variables. The random variable N takes positive integer values and has mean a and variance r. The random variables Xi are independent and identically distributed with mean b and variance s, and the random

31. Prob ans stat

Let x be a random variable that represents the length of time it takes a student to complete a take-home exam in Dr. Larson's psychology class. After interviewing many students, it was found that x has an approximately normal distribution with mean of 5.2

32. statistic

The random variable x represents the number of boys in a family with three children. Assuming that births of boys and girls are equally likely, find the mean and standard deviation for the random variable x.

33. math

A fair coin is flipped independently until the first Heads is observed. Let the random variable K be the number of tosses until the first Heads is observed plus 1. For example, if we see TTTHTH, then K=5 . For k=1,2,…,K , let Xk be a continuous random

34. ap stats

Continuous Random Variable, I Let X be a random number between 0 and 1 produced by the idealized uniform random number generator described. Find the following probabilities: a.P(0less than or equal to X less than or equal to 0.4) b.P(0.4 less than or equal

35. statistics

Identify the given item as probability distribution, continuous random variable, or discrete random variable. The amount of time that an individual watches television. a. discrete random variable b. probability distribution c. continuous random

36. probablity

We are given a biased coin , where the probability of heads is q. he bias q is itself the realization of a random variable Q which is uniformly distributed on the interval [0,1]. We want to estimate the bias of the coin. We flip it 5 times, and define

37. Probability

Let A,B,C be three events, and let X=IA, Y=IB, and Z=IC be the associated indicator random variables. We already know that X⋅Y is the indicator random variable of the event A∩B. In the same spirit, give an algebraic expression, involving X,Yand Z, for

38. probability

1) Let X and Y be independent continuous random variables that are uniformly distributed on (0,1) . Let H=(X+2)Y . Find the probability P(lnH≥z) where z is a given number that satisfies e^z

39. probability

Let X and Y be independent continuous random variables that are uniformly distributed on (0,1). Let H=(X+2)Y. Find the probability P(lnH≥z) where z is a given number that satisfies ez

40. statistics

the random variable x is normally distributed with a mean of 75 and a standard deviation of 15.0. For this distribution, what is the twenty-third percentile?

The random variable x is normally distributed with mean =1,000 and standard deviation =100. Sketch and find each of the following probabilities: P(x

42. statistic

X is a normally distributed random variable X with mean 15 and standard deviation 0.25. Find the values xL and xR of X that are symmetrically located with respect to the mean of X and satisfy P(xL < X < xR) = 0.80. (Hint. First solve the corresponding

43. Probability

Let N,X1,Y1,X2,Y2,… be independent random variables. The random variable N takes positive integer values and has mean a and variance r. The random variables Xi are independent and identically distributed with mean b and variance s, and the random

44. stats

Opisthotrochopodus n sp. is a polychaete worm that inhabits deep sea hydrothermal vents along the Mid-Atlantic Ridge. According to an article by Van Dover et al. in Marine Ecology Progress Series (1999, vol 181 pp 201-214), the lengths of female polychaete

45. probability

Let N,X1,Y1,X2,Y2,… be independent random variables. The random variable N takes positive integer values and has mean a and variance r. The random variables Xi are independent and identically distributed with mean b and variance s, and the random

46. Probability

Terminology: A circle of radius r is a curve that consists of all points at distance r from the center of the circle. A disk of radius r is the set of all points whose distance from its center is less than or equal to r . Thus, a circle is the boundary of

47. stats

Continuous Random Variable, I Let X be a random number between 0 and 1 produced by the idealized uniform random number generator described. Find the following probabilities: a.P(0less than or equal to X less than or equal to 0.4) b.P(0.4 less than or equal

48. statistics

Women’s heights are normally distributed with a mean of 162 cm and standard deviation of 16 cm. a. Define an random variable, X, and describe its full distribution including the mean and variance. b. What percentage of heights are greater than 180 cm ?

49. Math, statistics

Problem 1: The PDF of exp(X) (6/6 points) Let X be a random variable with PDF fX. Find the PDF of the random variable Y=eX for each of the following cases: For general fX, when y>0, fY(y)= Solution: f_x(ln(y))/y When fX(x) = {1/3,0,if −2

50. Probability

Let A,B,C be three events, and let X=Ia,Y=Ib, and Z=Ic be the associated indicator random variables. We already know that X.Y is the indicator random variable of the event A(intersection)B. In the same spirit, give an algebraic expression, involving X,Y

51. Statistics

Suppose X is a normally distributed random variable with the mean u(Mu) and variance sigma^2. Suppose P(X

52. Statistics

A random variable X is normally distributed with ì = 60. Convert the value of X to a z-score, if the standard deviation is as given. X = 60; ó = 7 A) 7 B) 1 C) 60/70 D) 0

53. Statistics

A random variable X is normally distributed with ì = 60. Convert the value of X to a z-score, if the standard deviation is as given. X = 60; ó = 7 A) 7 B) 1 C) 60/70 D) 0

54. probability

Problem 2. Continuous Random Variables 2 points possible (graded, results hidden) Let 𝑋 and 𝑌 be independent continuous random variables that are uniformly distributed on (0,1) . Let 𝐻=(𝑋+2)𝑌 . Find the probability 𝐏(ln𝐻≥𝑧) where

55. statistics

assume you have a data set from a normally distributed random variable. answer the following: will the random variable be discrete, continuous, or neither? How do you know? I believe its continuous but cant explain why will the data be qualitative or

56. Probability

In the following problem, please select the correct answer. Let X be a non-negative random variable. Then, for any a>0, the Markov inequality takes the form P(X≥a)≤(a^c)E[X^5]. What is the value of c? c= unanswered Suppose that X_1,X_2,⋯ are random

57. college ststistics

given x is a noramlly distributed random variable with a mean of 28 and a sd of 7 find p(x

58. Math

X is a normally distributed random variable with a mean of 8.00. If the probability that X is less than 9.54 is 0.67, then what is the standard deviation of X?

59. maths : probability

We are given a biased coin, where the probability of Heads is q. The bias q is itself the realization of a random variable Q which is uniformly distributed on the interval [0,1]. We want to estimate the bias of this coin. We flip it 5 times, and define the

60. Maths

The random variable X is normally distributed with mean 45 and standard deviation a.Given that P(X>51)=0.288, find the value of a.

61. stats

if x is a normally distributed random variable with amean of 8.00 if the proability for x is less than 9.54 is 0.67, then find the standard deviation of x

62. Math

Random variables X and Y are both normally distributed with mean 100 and standard deviation 4. It is known that random variable X+Y is also a normal distribution. a. What is the mean of X+Y? b. What is the standard deviation of X+Y? I see that the mean is

63. statistics

Let x be a continuous random variable that is normally distributed with a mean of 65 and a standard deviation of 15. Find the probability that x assumes a value less than 44.

64. Math

Random variable X is normally distributed with mean 10 and standard deviation 2. Compute the following probabilities. a. Pr(X

65. statistics

Let x be a continuous random variable that is normally distributed with a mean of 65 and a standard deviation of 15. Find the probability that x assumes a value less than 45.

66. ap stats need help

Continuous Random Variable, I Let X be a random number between 0 and 1 produced by the idealized uniform random number generator described. Find the following probabilities: a.P(0¡ÜX¡Ü0.4) b.P(0.4¡ÜX¡Ü1) c.P(0.3¡ÜX0.5) d.P(0.3(

67. statistics

Let X be a continuous random variable that is normally distributed with mean, µ = 15 and standard deviation, σ = 2.8, find a value xo that represents the 80th percentile of the distribution.

The random variable x is normally distributed with mean =1,000 and standard deviation =100. Sketch and find each of the following probabilities: P(x

69. Maths

The random variable X is distributed as B(200,0.7).Use the normal approximation to the binomial distribution to find P(136

70. Statistics/probability

The random variable X has a binomial distribution with the probability of a success being 0.2 and the number of independent trials is 15. The random variable xbar is the mean of a random sample of 100 values of X. Find P(xbar

71. Probability

7. The random variable X is distributed normally with a mean of 12.46 and variance of 13.11. You collect a random sample of size 37. a. What is the probability that your sample mean is between 12 and 13? b. What is the probability that a single observation

72. statistics

True or False: A zero population correlation coefficient between a pair of random variable means that there is no linear relationship between the random variable.

73. social psy

I want to utilize a true experimental design to study the effects of classical music exposure on the cognitive development of newborns. a- What is an independent variable? b- What is a dependent variable? c-What is random assignment? d-Why is random

74. Probability

Let Z be a nonnegative random variable that satisfies E[Z^4]=4. Apply the Markov inequality to the random variable Z^4 to find the tightest possible (given the available information) upper bound on P(Z≥2). P(Z>=2)

75. math

a fair coin is flipped 5 times the random variable is x is defined to be the number of heads that are observed identify the probability mass function of the random variable x. x P(x)

76. probablity

In this problem, you may find it useful to recall the following fact about Poisson random variables. Let X and Y be two independent Poisson random variables, with means λ1 and λ2, respectively. Then, X+Y is a Poisson random variable with mean λ1+λ2.

77. Statistics

Let X denote an exponential random variable with unknown parameter λ>0 . Let Y=I(X>5) , the indicator that X is larger than 5 . Recall the definition of the indicator function here is I(X>5)={1ifX>50ifX≤5. We think of Y as a censored version of the

78. statistics

Let x be a continuous random variable that is normally distributed with a mean of 24 and a standard deviation of 7. Find the probability that x assumes a value between 27.5 and 59.0. Use Table IV in Appendix C to compute the probabilities. Round your

79. Statistics

For a particular value, this table gives the percent of scores between the mean and the z-value of a normally distributed random variable. What percent of the total population is found between the mean and the z-score, assume z = 2.79

80. math

r a particular value, this table gives the percent of scores between the mean and the z-value of a normally distributed random variable. What percent of the total population is found between the mean and the z-score, assume z = 2.57.

81. Probability

Manhole explosions (usually caused by gas leaks and sparks) are on the rise in your city. On any given day, the manhole cover near your house explodes with some unknown probability, which is the same across all days. We model this unknown probability of

82. Statistics

For a particular value, this table gives the percent of scores between the mean and the z-value of a normally distributed random variable. What percent of the total population is found between the mean and the z-score, assume z = 2.57. PLEASA HELP!!!!

83. Statistics

If the population is normally distribution then the sample must be normally distributed even for small sample size? True or False. The variance of the standard normal distribution is always equal to 1.? True or False. A continuous random variable may not

84. probabilities

Let X be a Poisson random variable with µ = EX = 0.4 and let Y be another random such that E[(2Y + 1)2 ] = 10 and E[(Y − 1)2 ] = 4 Consider the random variable Z such that Z = 3X + 4Y + 2. 1. Find E(X2 ), E(Y 2 ) and E(Z). 2. Suppose that X and Y are

85. probablity

Let X and Y be two independent Poisson random variables, with means λ1 and λ2, respectively. Then, X+Y is a Poisson random variable with mean λ1+λ2. Arguing in a similar way, a Poisson random variable X with parameter t, where t is a positive integer,

86. Statistics

You would like to determine the percentage of coffee drinkers in your university, and collected the following binary data set from random students on campus, 1 for coffee drinker and 0 for otherwise: 0,0,0,1,1,0,1,0,1,1,1,1,0,0,0,1,0,1,0,0,0,0,0,1. Let Yi

87. Probability

Consider three random variables X, Y, and Z, associated with the same experiment. The random variable X is geometric with parameter p∈(0,1). If X is even, then Y and Z are equal to zero. If X is odd, (Y,Z) is uniformly distributed on the set

88. 1333 math

Probability Scores 0.2 0 0.2 2 0.05 4 0.45 7 0.1 9 Find the variance of the above random variable random variable.

89. Probability

Manhole explosions (usually caused by gas leaks and sparks) are on the rise in your city. On any given day, the manhole cover near your house explodes with some unknown probability, which is the same across all days. We model this unknown probability of

90. Probability

We are given a stick that extends from 0 to x . Its length, x , is the realization of an exponential random variable X , with mean 1 . We break that stick at a point Y that is uniformly distributed over the interval [0,x] . Find joint PDF fX,Y(x,y) of X

91. statistics

two dices are tossed once. let the random variable be t he sum of the up faces on the dice. A). find and graph the probability distribution of the random variable. and b) calculate the mean (or expectation) of this distribution

92. Math

the question i need help with is: Classify the random variable as finite discrete, infinite discrete or continuous. The random variable given is the number of hours a child watches television on a given day.

93. Statistics

I am so lost on this statistics question would someone help me figure out how to answer it? A random variable X is normally distributed with the mean and standard deviation 1.6. What is the proportion of the data values that lies within 1.6 standard

94. Statistics

Answer the following questions. ​(a) The random variable x is distributed​ normally, with x~N(80,100) Find the probability that x is greater than 90. x >90. ​(b) Find P(x

95. statistics

The average age of statistics students nationwide is 22. The standard deviation is 2.5 years. Assume the age is a normally distributed variable. Find the probability that one student selected at random is older than 23. Find the probability that the mean

96. Math

6. Biased coin Bookmark this page Problem 5. Biased coin 5.0 points possible (graded, results hidden) We are given a biased coin, where the probability of Heads is q. The bias q is itself the realization of a random variable Q which is uniformly

97. Calculus

Suppose X is a random variable whose CDF is given by F(x) = 0, X

98. STATS

. The time to fly between New York City and Chicago is normally distributed with a mean of 180 minutes and a standard deviation of 17 minutes. What is the z-score that corresponds to a random variable X outcome of 190 minutes?

99. Maths

The Random Variable X is normally distributed with mean 560 and standard deviation 20. Find P(X

100. Maths

The Random Variable X is normally distributed with mean 560 and standard deviation 20. Find P(X