In a survey 172 respondents say that they never use a credit

In a survey. 172 respondents say that they never use a credit card. 1232 say that they use it sometimes. and 2839 say that they use it frequently. What is the probability that a randomly selected person uses a credit card frequently? Is it unlikely for someone to use a credit card frequently? How are ail of these results affected by the fact that the responses were obtained by those who decided to respond to a survey posted on the Internet? The probability that a randomly selected person uses a credit card frequently is Is it unlikely for someone to use a credit card frequently?

Solution

1) P = 2839/(172+1232+2839) = 0.669

2) (C)

3) (A)