Answer: .
Step-by-step explanation:
Given : Sample size : n= 64 , the sample is a large sample (n>30), so we can apply z-test.
Sample mean =
Standard deviation :
Level of confidence:
Then, critical z-value =
The confidence interval to estimate the population mean is given by :_
Hence, the 95% confidence interval to estimate the population mean can be computed as .
Answer:
Step-by-step explanation:
Given that X has the following pdf.
x -1 0 2 6 7 Total
P(X) 0.3 0.1 0.3 0.2 0.1 1
xP(X) -0.3 0 0.6 1.2 0.7 2.2
x^2P(X) 0.3 0 1.2 7.2 4.9 13.6
Var(x) 13.6-2.2^2 8.76
Std dev 2.959729717
5)
6. Find the cumulative distribution function F(x) and calculate F(3.2) =
x -1 0 2 6 7
P(X) 0.3 0.1 0.3 0.2 0.1
F(x) 0.3 0.4 0.7 0.9 1
F(3.2) = P(X<3.2) = ___F(X<6) = 0.7__________
7. E(X) = ______2.2_____
8. Var(X) = ____8.76______