7.11
A. The shape should be approximately shape because the central intend theorem. The sample size could be considered epic so the sampling distribution will be normal.
B. The pie-eyed is the same as the population mean, 20.
The standard deviation is 4/sqrt(64) = 4/8 = 0.5
C. z = (xbar - mu)/(sigma/?n)
z = (21 - 20)/(4/?64)
z = 1 / 0.5
z = 2
p = 0.9772
p = 1 - 0.9772 = 0.0228
D. z = (xbar - mu)/(sigma/?n)
z = (19.385 - 20)/(4/?64)
z = -0.615 / 0.5
z = -1.23
p = 0.1093
7.30
A. z = (phat - p)/sqrt[p (1-p)/n]
z = (0.32 - 0.3) / sqrt [0.3(1 - 0.3)/1011]
z = 0.02 / sqrt (0.00020772)
z = 1.421
p = 0.9223
Since we want greater than, p = 1 - 0.9223 = 0.0777
B. Maybe, but we did not set an Alpha level sooner beginning.
8.8
A. if ? = 0.05 then CI (95%) for the mean is 5.46±z(0.025)2.47/?100 = (4.976,5.944)
if ? = 0.
01 then CI (99%) for the mean is 5.46±z(0.005)2.47/?100 = (4.824,6.096)
B. Yes, because the upper limit (5.944) < 6
C. No, because the upper limit (6.096) >6
D. We are 95% confident that the mean is less than 6
8.38 95% confidence interval:
p +/- z * sqrt [p(1 - p)/n]
0.5571 +/- 1.96 * sqrt [( 0.5571 * 0.4429)/350]
0.5571 +/- 1.96 * sqrt [0.00070496]
0.5571 +/- 0.05204
(0.5051, 0.6092)
Since 0.48 is not at bottom the confidence interval, we can be 95% certain that the true(a) proportion is above 0.48If you want to get a wide of the mark essay, order it on our website: Orderessay
If you want to get a full essay, wisit our page: write my essay .
No comments:
Post a Comment