Question

A recent article in the paper claims that business ethics are at an all-time low. Reporting on a recent sample, the paper claims that 31% of all employees believe their company president possesses low ethical standards. Suppose 20 of a company's employees are randomly and independently sampled and asked if they believe their company president has low ethical standards and their years of experience at the company. Could the probability distribution for the number of years of experience be modelled by a binomial probability distribution?

Answer 1

Answer:

The correct solution is "0.127128".

Step-by-step explanation:

The given values are:

p = 0.31

n = 20

Now,

$p(8<x<12)=p(x=9)+p(x=10)+p(x=11)$

                     $=20C_{9}(0.31)^9\times (0.69)^{11}+20C_{10}(0.31)^{10}\times (0.69)^{10}+20C_{11}\times (0.31)^{11}\times (0.69)^{9}$

$=0.074955+0.037043+0.015130$

$=0.127128$