# Questions on probability distributions - Binomial, Poisson

1 The Kwik Klean Car Wash loses $30 on rainy days and gains $120 on days when it does not rain. If the probability of rain is 0.15, what is the expected value of net profit?

2. The Newman Construction Company bids on a job to construct a building. If the bid is won, there is a 0.7 probability of making a $175,000 profit and there is a probability of 0.3 that the contractor will break even. What is the expected value?

3. Assume that in a binomial experiment, a trial is repeated n times. Find the probability of x successes given the probability p of success on a given trial with n = 12, x = 7 and p = 0.4. (Use Table A-1)

4. Several students are unprepared for a true/false test with 50 questions, and all of their answers are guesses. Find the mean, variance and standard deviation for the number of correct answers for such students.

5. A statistics professor finds that when she schedules an office hour for student help, an average of two students arrive. Find the probability that in a randomly selected office hour, the number of student arrivals is five.

https://brainmass.com/statistics/probability/questions-on-probability-distributions-binomial-poisson-4604

#### Solution Preview

1. The Kwik Klean Car Wash loses $30 on rainy days and gains $120 on days when it does not rain.

If the probability of rain is 0.15, what is the expected value of net profit?

Expected profit=15%*(-30)+(1-15%)*(120)=

$97.50

2. The Newman Construction Company bids on a job to construct a building.

If the bid is won, there is a 0.7 probability of making a $175,000 profit and there is a probability

of 0.3 that the ...

#### Solution Summary

The solution provides answers to questions on probability distributions - binomial, Poisson.