# Normal probability calculation

#1

The average number of customer complaints at the Full Moon Motel is five per day.

Find the probability that on a typical day, the motel will receive

a) eight complaints

b) at least two complaints

#2

Demand for a product is normal, with mean being 400 and standard deviation being 25 units. Find

a) Pr (demand > 445)

b) Pr (demand is between 375 and 425)

c) Pr (demand equals 400)

d) Pr (demand exceeds 500)

e) The 5 percentile demand level

#3The sales of a product are uniformly distributed between 300 and 800. Find

a) Probability (Sales < 500)

b) Probability (Sales between 700 and 900)

c) Probability of sales exactly equal to 750

d) 15 percentile sales level

https://brainmass.com/statistics/probability-density-function/normal-probability-calculation-142214

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Statistics Business

#1 The average number of customer complaints at the Full Moon Motel is five per day.

Find the probability that on a typical day, the motel will receive

a) Eight complaints

b) At least two complaints

Answer

Let X be the number of complaints at the Full Moon Motel. Given that X is Poisson with mean = 5. The probability density function of Poisson random variable is given by

The probabilities for different values of X are given below

X P(X=x)

0 0.006737947

1 0.033689735

2 0.084224337

3 0.140373896

4 0.17546737

5 0.17546737

6 0.146222808

7 0.104444863

8 0.065278039

9 0.036265577

a). P(X=8) = 0.065278039

b). ...

#### Solution Summary

This solution gives the step by step method for computing probability from normal distribution.