Statistics and Probability Answers

It is known that in a glass items production in the average one in every 1000 items contain bubbles. Assuming Poisson’s distribution, find the probability that in 6000 items: (a) Exactly 5 items contain bubbles. (b) Less than 4 items contain bubbles

The probability of a telesales representative making a sale on a customer call is 0.15. find the probability that No sales are made in 10 calls and More than 3 sales are made in 20 calls

In a large restaurant an average of 3 out of every 5 customers ask for water with their meal. A random sample of 10 customers is selected. Find the probability that Exactly 6 ask for water with their meal and Less than 9 ask for water with their meal

The loss due to an earthquake in a commercial building is modelled by a random variable X with density function

An archer shoots arrows at a circular target where the central portion of the target
inside is called the bull. The archer hits the bull with probability 1/32. Assume that
the archer shoots 96 arrows at the target, and that all shoots are independent
(a) Find the probability mass function of the number of bulls that the archer hits.
(b) Give an approximation for the probability of the archer hitting no more than one
bull.
Examiners

A7. A recent study shows that the annual cost of maintaining a building in Accra averages
200 Cedis with a variance of 260 Cedis. If a tax of 30% is introduced on all items
associated with the maintenance of building i.e. everything is made 30% more expensive.
Calculate the standard deviation of the annual cost of maintaining a building in Accra

A package of 6 fuses are tested where the probability an individual fuse is defective is 0.5
What is the probability that one fuse will be defective

A package of 6 fuses are tested where the probability an individual fuse is defective is
0.05. (That is, 5% of all fuses manufactured are defective).
(a) What is the probability one fuse will be defective?
(b) What is the probability at least one fuse will be defective?
(c) What is the probability that more than one fuse will be defective, given that at
least one is defective?

. Find the value of Z if the normal curve area between 0 and Z (positive) is 0.4332.

2. Find the area under the standard normal distribution which lies between Z = -0.45 and Z = 0.75?