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Probability- lifetime of light bulbs

A certain factory has three machines A,B and C that produces one type of light bulbs.Past experience has shown that the lifetime of a light bulb by machine A can be modeled as an exponential random variable with an average of 20 days, whereas the lifetime of a bulb produced by a machine B can modeled as a normal random variable

Geometry : Probability that Three Points on a Circle will form a Right-Triangle

If n points are equally spaced on the circumference of a circle, what is the probability that three points chosen at random will form a right triangle? I know that for us to have a right triangle, the two points should form the diameter of the circle. What I have done is that I divided the problem into two sections. Section

Find an approximate 95% confidence interval for the mean of this distribution

It was suggested that the number of particles in a randomly selected interval might follow a Poisson distribution. Assuming a Poisson distribution to be an appropriate model for the data, use two methods to find an approximate 95% confidence interval for the mean of this distribution. See attachment for full question includin

A sample of n independent observations...

Please see the attached file for full problem description. --- ? A sample of n independent observations are obtained of a random variable having a Poisson distribution with mean . Show that the maximum likelihood estimate of is he sample mean show that the corresponding estimator is an unbiased estimator of , and h

Dice problem involving probability

Constuct an unique pair of dice (6 sides) so that each of the sums 2 through 12 has an equal (nonzero i.e. cannot have two dice with all zero's) probability of occurring. The dice do not have to be identical.


Question 1 A restaurant can serve up to 75 meals. Experience shows that 20% of clients who have booked do not turn up. 1. The manager accepts 90 bookings. What is the probability that more than 50 clients turn up? 2. How many bookings should the manager accept in order to have a probability of more than 0.9 that he will s

Probability : Void Suit in a Bridge Hand

In the game of bridge, a player is dealt a hand of 13 playing cards from a standard 52 card deck. A hand is said to have a void in a suit if it contains no cards in that suit. Determine the number of distinct hands containing at least one void. What is the probability of being dealt a hand with at least one void? Your answer sho


4.19) The lifetimes of two car batteries (Brand A and B) are independent exponential random variables with means 12 hours and 10 hours, respectively. What is the probability that Brand B battery outlasts Brand A battery?


3.21) Suppose a machine has three independent components with Exp(.1) lifetimes. Compute the expected lifetime of the machine if it needs all three components to function properly. (This is a multivariate random variable problem)

Probability : k-out-of-n System

2.54) Consider the k-out-of-n system (explanation: a system consists of n independent components. Each component functions with probability p. The system as a whole functions if at least k components are functioning (1 <= k <= n)). Suppose we visit this system at time t=3 and replace all failed components, at a cost of $75 eac

Probability : Random Selection

Suppose there are two vendors and each provides 50% of the items. The lifetime (in days) of an item from the first vendor is Exp(.1), and that from the second vendor is Exp(.08). Compute the probability that a randomly picked item will last more than 12 days.

What is the probability that the kth shock kills the machine?

2.20) Suppose a shock causes a unit damage to the machine with probability 0.1 and no damage with probability of 0.9. Successive shocks are independent. Suppose the damages are cumulative and the machine can withstand at most four units of damage. (That, is the machine fails when the fifth unit of damage is inflicted on it.) Wha


2.16) Consider the k-out-of-n system (info on the system: A system consists of n independent components. Each component functions with probability p. The system as a whole functions if at least k components are functioning (1 <= k <= n)). The probability that a component is functioning at time t is given to be e^(-t). Comput

Probability using Bayes theorem

1.22) An oil executive has determined that the probability that this oil field contains oil is 0.6. Before starting the drilling she decides to order a seismological test to see if there is oil in the ground. Unfortunately, the test is not entirely accurate. It concludes that there is oil with probability 0.9 if there is indeed


In the questions I have below it says a bowl has eight ping pong balls numbered 1,2,2,3,4,5,5,5. You pick a ball at random. a. Find p(the number on the ball drawn is &#8805; 3). b. Find p(the number on the ball drawn is even).


A jar contains 8 red marbles, 9 blue marbles, and 6 green marbles. Two marbles are chosen at random. What is the probability that one is green and the other is blue?


Let E and F be non-zero-probability events. If E and F are mutually-exclusive, can they also be independent? Explain the answer, and also prove it algebraically using the definitions of mutually-exclusive and independent events.


If E and F are events with P ( E U F ) = 5/8, P (E &#8745; F = 1/3, and P (E) = ½, Find: (a) P(E) (E has a straight line over it) (b) P (F) (c) P (F) (F has a straight line over it) detail each answer: (a) ½ (b) 11/24 (c) 13/24


An experimental test to detect a particular type of cancer indicates the presence of cancer in 90% of individuals known to have this type of cancer, and in 15% of individuals known to be cancer-free (false positive). One hundred individuals volunteer to take the test. Of the 100, 60 are known to have the cancer, and 40 are known

Probability : Target Shooting

An archer has probability 0.3 of hitting a certain target. What is the probability of hitting the target exactly two times in four attempts?

Probability : Random Selection

In a carnival game the players selects two coins from a bag containing two silver dollars and six slugs. Write down the probability distribution for the winnings and determine how much the player would have to pay so that he would break even, on the average, over many repetitions of the game.


Forty percent of a particular model of car are silver. What is the probability that in the next 10 observations of this model you observe 5 silver cars?

Determine Probability Distribution

In a certain carnival game a player pays $1 and then tosses a fair coin until either a "head" occurs or he has tossed the coin four times. He receives fifty cents for each toss. Determine the probability distribution for the experiment of playing the game and observing the player's earnings.