Question:Hi, Could you please answer the following questions with ALL WORKING? I really focused on the working out of the answers.

21.The expected number of heads in 150 tosses of an unbiased coin is:

22.If the random variableXis normally distributed with a mean of 60 and a variance of 100, thenP(X> 66) is:

23.If E(X²) is 14 and the standard deviation ofXis 2, what is the value of the expected value ofX?

24.The number of books sold monthly at a campus bookstore is uniformly distributed with a minimum of 300 and maximum of 450 books. What is the probability that the bookstore will sell at least 420 books?

25.What proportion of the data from a normal distribution is within 1.5 standard deviations of the mean?

a.

0.5467

b.

0.7525

c.

0.8664

d.

0.9656

26. The average weight for a group of 40 staff members in the same office is 75 kilograms. The 20 female staff in the office average 70 kilograms. The male staff in the office average:

27.Given thatZis a standard normal random variable,P(-1.30 <Z< 1.87) is:

28.IfXandYare two independent random variables with V(X) = 4, V(Y) = 3 and COV(X,Y) = 1, then V(2X- 3Y) is: