# Probability, Poisson distribution, Normal Distribution

1. Meagan Dubean manages a portfolio of 200 common stocks. Her staff classified the portfolio stocks by 'industry sector' and 'investment objective.'

Investment objective Industry Sector

Electronics Airlines Healthcare Total

Growth 84 21 35 140

Income 36 9 15 60

Total 120 30 50 200

Are "Healthcare" and "Income" independent and why or why not?

a. yes, because P(Income intersection Healthcare) 0

b. no, because P(Income intersection Healthcare) = P(Healthcare) ? P(Income)

c. yes, because P(Healthcare | Income) = P(Healthcare)

d. no, because P(Healthcare) not equal to P(Income)

2. If lambda is 3 occurrences per five minute time interval, the probability of getting 5 occurrences over a five minute interval is _______.

a. 0.1500

b. 0.0940

c. 0.1008

d. 0.0417

3. Brian Vanecek, VP of Operations at Portland Trust Bank, is evaluating the service level provided to walk-in customers. Accordingly, his staff recorded the waiting times for 64 randomly selected walk-in customers, and determined that their mean waiting time was 15 minutes and that the standard deviation was 4 minutes. The 95% confidence interval for the population mean of waiting times is ________.

a. 7.16 to 22.84

b. 14.06 to 15.94

c. 8.42 to 21.58

d. 13.88 to 16.12

https://brainmass.com/statistics/probability/probability-poisson-distribution-normal-distribution-83519

#### Solution Preview

1. Meagan Dubean manages a portfolio of 200 common stocks. Her staff classified the portfolio stocks by 'industry sector' and 'investment objective.'

Investment objective Industry Sector

Electronics Airlines Healthcare Total

Growth 84 21 35 140

Income 36 9 15 60

Total 120 30 50 200

Are "Healthcare" and "Income" independent and why or why not?

a. yes, because P(Income intersection Healthcare) 0

b. no, because P(Income intersection Healthcare) = P(Healthcare) ? P(Income) ...

#### Solution Summary

Answers multiple choice questions on probability, Poisson distribution, Normal Distribution.