probability mass function of X is as follows:
P(X=1)=P(at least one dice shows 1)=1-P(none of both shows 1)=1-(5/6)*(5/6)=11/36
P(X=2)=P(both dice are at least 2 and at least dice shows a 2) =9/36
P(X=3)=7/36
P(X=4)=5/36
P(X=5)=3/36
P(X=6)=1/36
hence
P(X>3)=P(X=4)+P(X=5)+P(X=6)=(5/36)+(3/36)+(1/36)=9/36=1/4
3. Two fair dice are thrown. Let X be the smaller of the two numbers obtained...
Question 5: Roll two fair dice and let X be the sum of the two numbers faced up. a. Find the probability distribution of X . b. What is the expected value of X? c. What is the variance of X ?
(20pts) Problem 3. A pair of fair dice are cast, and the number of rolled dots, on each die, is recorded. Let X denote the difference of the two numbers (10pts)a. Find the probability mass function of X. b. Find the expected value E(X).
2. Let X1 and X2 be the numbers showing when two fair dice are thrown. Define new random variables XX1 - X2 and Y -X1 + X2. Show that X and Y are uncorrelated but not independent. Hint: To show lack of independence, it is enough to show that PX = j, Y = k]メPX = j] . P[Y = 서 for one pair (j, k); try the pair (0.2).]
1. Two fair dice are thrown and the smallest of the face values, Z say, is noted (a) Give the probability mass function (pmf) of Z in table form: P(Z=2) (b) Calculate the expectation of 1/Z 2] (c) Consider the game, where a player throws two fair dice, and is paid Z dollars, with Z as above. To enter the game the player is required to pay 3 dollars What is the expected profit (or loss) of the player, if...
.1. A pair of fair dice is thrown, what is the probability that the sum of the two numbers is greater than 10. 2. A pair of fair dice is thrown. Find the probability that the sum is 9 or greater if a. If a 6 appears on the first die. b. If a 6 appears on at least one of the dice.
Part I - Throwing a Dice with Six Faces (32 points) Consider a dice with six faces, i.e. a standard dice. The possible outcomes after throwing the dice once are 1, 2,3, 4,5,6 (a) Assume that the dice is thrown once. Let w represents the outcome. Explain why P(w-i) for i = i..6, when the dice is fair (b) The fair dice is thrown twice. Find the probability of occurance of at least one 6 The fair dice is thrown...
2. Let X1 and X2 be the numbers showing when two fair dice are thrown. Define new random variables X = Xi-X2 and Y = X1 + X2. Show that X and Y are uncorrelated but not independent. Hint: To show lack of independence, it is enough to show that PlX = j, Y = k]メPIX = j] . PY = k] for one pair (j, k); try the pair (0.2).]
Two fair dice are thrown. What is the probability of at least one odd number? What is the probability of this if four fair dice are thrown?
Exercise 10.17. We flip a fair coin. If it is heads we roll 3 dice. If it is tails we roll 5 dice. Let X denote the number of sixes among the rolled dice. (a) Find the probability mass function of X. (b) Find the expected value of X.
The expected sum of two fair dice is 7; the variance is 35/6. Let X be the sum after rolling n pairs of dice. Use Chebyshey's inequality to find z such that P(|X – 7n< z) > 0.95. In 10,000 rolls of two dice there is at least a 95% chance that the sum will be between what two numbers?