Statistics and Probability Answers

P(z < -0.73)

P(z > 2.92)

P(z < -0.73)

P(0 < z < z⁰)=0.1700

P(1.12 < z < 1.39)

Prove that the probability of P(A/B)=0

A factory employer claims that their company follows the hours

of work for its employees and the standard deviation of their

working time is 0.5 hours.

It is given that the total marks of all probability students have an average of 45 marks with a standard deviation of 15 marks. If a student from a sample of 9 students is chosen at random, what is the probability that his marks are between 40 and 60?

A canteen owner claims that the average meal cost of his usual clients is

Php180. In order to test his own claim, he took a random sample of 30

receipts and computed the mean cost of Php210 with a standard deviation of

Php25. Test the hypothesis at 0.01 level of significance. Show all steps

A company that supplies ready-mix concrete receives, on average, six orders per day.

(a) What is the probability that, on a given day:

(i) only one order will be received?

(ii) no more than three orders will be received?

(iii) at least three orders will be received?

(b) What is the probability that, on a given half-day, only one order will be received?

(c) What is the mean and standard deviation of orders received per day?