Ten years ago,only 15% of the U.S.population consisted of people more than 65 years old.A researcher plans to use a sample of n = 300 people to determine whether the population distribution has changed during the past ten years.If a chi-square test is used to evaluate the data,what is the expected frequency for the older-than-65 category?
A)15
B)30
C)45
D)150

Question

​Ten years ago,only 15% of the U.S.population consisted of people more than 65 years old.A researcher plans to use a sample of n = 300 people to determine whether the population distribution has changed during the past ten years.If a chi-square test is used to evaluate the data,what is the expected frequency for the older-than-65 category?
A)​15
B)​30
C)​45
D)​150

Quizplus · Accepted Answer

The expected frequency is calculated by multiplying the sample size (n = 300) by the proportion of the population in the category of interest (15% or 0.15). Thus, 300 * 0.15 = 45.

​Ten Years Ago,only 15% of the U

Ten Years Ago,only 15% of the U