The UMUC MiniMart sells four different types of teddy bears. The manager reports that the

four types are equally popular. Suppose that a sample of 500 purchases yields observed counts 150,

120, 110, and 120 for types 1, 2, 3, and 4, respectively.

Type 1 2 3 4

Number 150 120 110 120

Assume we want to use a 0.05 significance level to test the claim that the four types are

equally popular.

(a) Identify the null hypothesis and the alternative hypothesis.

(b) Determine the test statistic. Show all work; writing the correct test statistic, without

supporting work, will receive no credit.

(c) Determine the critical value. Show all work; writing the correct critical value, without

supporting work, will receive no credit.

(d) Is there sufficient evidence to support the managers claim that the four types are equally

popular? Justify your answer.