​Ten Years Ago,only 15% of the U

Multiple Choice

​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