Question

a cbs news poll involved a nationwide random sample of 651 affiliation (democrat, republican or none) and their opinion on whether things are getting better, getting worse or about the same. the results are shown in the following table:

	better	same	worse
democrat	12	87	137
none	21	90	118

if we randomly select one of the adults who participated in this poll, find the following probabilities (accurate to at least 4 decimal places):
a. p(republican) = 0.2857
b. p(worse) = 0.4624
c. p(worse|republican) = 0.2366
d. p(republican|worse) = 0.147
e. p(republican and worse) = 0.0676

Explanation:

Step1: Calculate total number of participants

Sum all the values in the table: $38 + 104+44 + 12+87 + 137+21+90+118=651$.

Step2: Calculate P(worse)

Find the total number of people who think it's worse: $44 + 137+118 = 300$. Then $P(\text{worse})=\frac{300}{651}\approx0.4608$.

Answer:

$0.4608$