A) In a particular telephone poll, useful information has been obtained on 40 percent of the calls. A pollster makes ten calls. What is the probability that
At least four calls are productive?
Six or more calls are unproductive?
What is the expected number of productive call?
B) If electricity power failures occur according to a Poisson distribution with an average of 3 failures every twenty weeks, calculate the probability that there will not be more than one failure during a particular week.
C) A small company estimates that its net profit for the year will be between $100,000 and $120,000. It believes that the actual value is equally likely to fall anywhere within that range. What is the probability that the annual net profit will be:
Over $114,000?
In the range between $109,500 and $112,000?
D) The best information regarding the cost of a research project is that it is normally distributed with a mean of $50,000 and a standard deviation of $5,000. The available funds are limited to $60,000. What is the probability that the project costs
Will not exceed the available funds?
Will be between $40,000 and $55,000?
Will be more than $45,000?
what is the cost which
4. Will not be exceeded more that 15% of the time ?
5. Will be exceeded 95% of the time ?
E) The lifetime of an electronic component in a citizen’s band radio has an exponential distribution with a mean of two years. What is the probability tht the component lasts at least
One year?
Two years?
Three years?