It is estimated that 46 percent of the callers to the Custom

It is estimated that .46 percent of the callers to the Customer Service department of Dell Inc. will receive a busy signal.

What is the probability that of today\'s 1000 callers at least 5 received a busy signal? Use the poisson approximation to the binomial. (Round your answer to 4 decimal places.)

Solution

It is estimated that 0.46 percent of the callers to the Customer Service department of Dell Inc. will receive a busy signal.

What is the probability that of today\'s 1000 callers at least 5 received a busy signal? Use the poisson approximation to the binomial. (Round your answer to 4 decimal places.)

0.46 percent of the callers to the Customer Service department of Dell Inc. will receive a busy signal.

P=0.46/100 =0.0046

\\lambda= np=1000*0.0046=4.6

Mean/Expected number of events of interest: 4.6

POISSON.DIST Probabilities Table

X

P(X)

0

0.0101

1

0.0462

2

0.1063

3

0.1631

4

0.1875

P( x >=5)

=( 1- P( x <5))

= ( 1-(P( x=0)+ P( x=1)+ P( x=2)+ P( x=3)+ P( x=4))

=(1-( 0.0101+ 0.0462+ 0.1063+ 0.1631+ 0.1875)

1-0.5132

=0.4868