In the year 2000 approximately 20 of Americans reported eati

In the year 2000, approximately 20% of Americans reported eating fast food more than three times per week. A researcher plans to use a sample of n = 400 people to determine whether the population distribution has changed since that time. If a chi-square test is used to evaluate the data, what is the expected frequency for the number of Americans eating fast food more than three times per week?

Solution

Expected number will be n*p = 400*0.2 = 80