Question

d.)Let X be a discrete random variable equal to the number of girls you have out...

d.)Let X be a discrete random variable equal to the number of girls you have out of 6 children.

What is P(X=2 | X=1)

P(X=2∣X=1)?

a.) Assume that a website allows only lower case letters for password required to have a length of size 5, but does not allow the following choices for the password: (1) all 5 characters are identical and (2) any sequence ending with "gk". If a 5 letter sequence is randomly selected, what is the probability that it is a valid password?

Homework Answers

Answer #1

(d) P(X=2 | X=1) = P(X = 2 X = 1) / P(X = 1)

Since X =2 and X = 1 cannot occur simultaneously, hence P(X = 2 X = 1) = 0

=> P(X=2 | X=1) = 0

(a)

Valid passwords = Total passwords - passwords with all identical characters - password ending with "gk"

Total passwords

5 characters each with 26 possible cases => (26)5

passwords with all identical characters

Choose any letter and make a password with all identical characters => 26

password ending with "gk"

Any character for first three positions and gk for last two positions

=> 26*26*26 = (26)3

Valid passwords = (26)5 - 26 - (26)3

Know the answer?
Your Answer:

Post as a guest

Your Name:

What's your source?

Earn Coins

Coins can be redeemed for fabulous gifts.

Not the answer you're looking for?
Ask your own homework help question
Similar Questions
Let the random variable x represent the number of girls in a family with three children....
Let the random variable x represent the number of girls in a family with three children. Assume the probability of a child being a girl is 0.42. The table on the right describes the probability of having x number of girls. Determine whether the table describes a probability distribution. If it​ does, find the mean and standard deviation. Is it unusual for a family of three children to consist of three​ girls? x | P(x) 0 | 0.195 1 |...
Q6/   Let X be a discrete random variable defined by the following probability function x 2...
Q6/   Let X be a discrete random variable defined by the following probability function x 2 3 7 9 f(x) 0.15 0.25 0.35 0.25 Give   P(4≤  X < 8) ــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــ Q7/ Let X be a discrete random variable defined by the following probability function x 2 3 7 9 f(x) 0.15 0.25 0.35 0.25 Let F(x) be the CDF of X. Give  F(7.5) ــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــ Q8/ Let X be a discrete random variable defined by the following probability function : x 2 6...
Let x be a discrete random variable with the following probability distribution x: -1 , 0...
Let x be a discrete random variable with the following probability distribution x: -1 , 0 , 1, 2 P(x) 0.3 , 0.2 , 0.15 , 0.35 Find the mean and the standard deviation of x
Let X be a discrete random variable with positive integer outputs a show that p (X=...
Let X be a discrete random variable with positive integer outputs a show that p (X= K)= P( X> K-1) - P( X> k) for any positive integer k b Assume that for all k >I we have P (X>k)=q^k  use l() to show that X is a geometric random variable
Let the random variable X have a discrete uniform distribution on the integers 1 ≤ x...
Let the random variable X have a discrete uniform distribution on the integers 1 ≤ x ≤ 7. Determine the mean, μ, and variance, σ2, of X. Round your answers to two decimal places (e.g. 98.76). μ = σ2 =
let x be a discrete random variable with positive integer outputs. show that P(x=k) = P(...
let x be a discrete random variable with positive integer outputs. show that P(x=k) = P( x> k-1)- P( X>k) for any positive integer k. assume that for all k>=1 we have P(x>k)=q^k. use (a) to show that x is a geometric random variable.
1. Let X be a discrete random variable with the probability mass function P(x) = kx2...
1. Let X be a discrete random variable with the probability mass function P(x) = kx2 for x = 2, 3, 4, 6. (a) Find the appropriate value of k. (b) Find P(3), F(3), P(4.2), and F(4.2). (c) Sketch the graphs of the pmf P(x) and of the cdf F(x). (d) Find the mean µ and the variance σ 2 of X. [Note: For a random variable, by definition its mean is the same as its expectation, µ = E(X).]
Let LaTeX: X,YX , Y be two discrete random variables that have the following joint distribution:...
Let LaTeX: X,YX , Y be two discrete random variables that have the following joint distribution: x = 0   1 y = -1   0.18   0.12 0   ?   0.20 1   0.12   0.08 (a) Determine the following probabilities: LaTeX: P(X=0, Y=0) P ( X = 0 , Y = 0 ), LaTeX: P(X\le 0,Y\le 0)P ( X ≤ 0 , Y ≤ 0 ) (b) Find the marginal distribution of LaTeX: YY. (c) What is the conditional distribution of LaTeX: XX given...
Question 1 (General Discrete) Household Size from U.S. Census of 2010 Let X be the random...
Question 1 (General Discrete) Household Size from U.S. Census of 2010 Let X be the random variable: number of people (persons!) in a household. Number of people in household (x) Probability P(X=x) xP(x) x-μ x-μ2 P(x)x-μ2 1 0.267 2 0.336 3 0.158 4 0.137 5 0.063 6 0.024 7 0.015 Totals: Confirm that this is a probability distribution. Draw a bar chart. Is the distribution symmetric, left or right skewed? Calculate the mean and standard deviation. What is the probability...
1. A coin is tossed 3 times. Let x be the random discrete variable representing the...
1. A coin is tossed 3 times. Let x be the random discrete variable representing the number of times tails comes up. a) Create a sample space for the event;    b) Create a probability distribution table for the discrete variable x;                 c) Calculate the expected value for x. 2. For the data below, representing a sample of times (in minutes) students spend solving a certain Statistics problem, find P35, range, Q2 and IQR. 3.0, 3.2, 4.6, 5.2 3.2, 3.5...
ADVERTISEMENT
Need Online Homework Help?

Get Answers For Free
Most questions answered within 1 hours.

Ask a Question
ADVERTISEMENT