Statistics and Probability Answers

Emmanuel is given a multiple-choice exam with ten questions and each question with
five possible answers. He decided to guess randomly for each question. What is the
probability that he will get at least six questions correct?

The mean number of errors due to a bug occurring in a minute is 0.0001. What is the probability that no error will occur in 20 minutes?

In a bolt manufacturing factory, machines A,B, and C produce 25%, 30% and 45% of the total output, respectively. Of their outputs, 7%,6% and 4% are defective bolts, respectively. If a bolt drawn at random from the production is found to be defective, what is the probability that it was manufactured by machine C?

A random variable X has Poisson distribution with mean equal to 0.4. What is the probability that the random variable is greater than zero?

A discrete random variable has a probability mass function of P(X=n) = 0.5*n.
Let Y = 1 for x even and -1 for x odd ...
What is the expected value of Y

A discrete random variable has probability mass function, P(X = n) = 12
n.
Let Y =  1, for x even
 1, for x odd
Find the expected value of Y ; (E[y]).

A baseball team has scheduled its opening game for April 5. It is assume that if it
snows on April 5, the game is postponed and will be play on the next day that it
does not snow. The team purchased insurance against snow. The policy will pay GHS
1,000 for each day, up to 2 days that the game is postponed. It is determined that
the number of consecutive days of snow beginning on April 1, is a Poisson random
variable with mean 0.6. What is the expected cost to the nearest one Ghana cedi that
the insurance company will have to pay?

. A random variable X has Poisson distribution with mean equal to 0.4. What is the
probability that the random variable is greater than zero?

Suppose Komla throws a die repeatedly until he gets a six. What is the probability
that he needs to throw more than 10 times to get a six, to 3 decimal places?

The mean number of errors due to a bug occurring in a minute is 0.0001. what is the probability that no error occur in 20 minutes