It was found that the 80% of seniors at specific college had accepted the job offer before graduation. For those accepting offers, salary distribution was normal with mean $29,000 and standard deviation $4,000.
a) For random sample of 60 seniors determine the probability that less than 70% have accepted job offers?
b) For a sample of 6 senior who have accepted job offers determine the probability that the average salary is more thatn $30,000?