Consider the approximately normal population of weights of female college studen
ID: 3200407 • Letter: C
Question
Consider the approximately normal population of weights of female college students with mean of 118 pounds and standard deviation of 6.8 pounds. A random sample of 16 weights is obtained.
23. Describe the distribution of x, weight of female college student.
ANSWER:
24 .Find the proportion of female college students whose weight is greater than 120 pounds.
ANSWER: z = (x-)/ = (120-118)/6.8 = 0.294
25. Describe the distribution of, the mean of samples of size 16.
ANSWER:
26. Find the mean and standard error of the distribution.
ANSWER:
27. Find the probability that the sample mean weight exceeds 121 pounds.
ANSWER:
28. Find the probability that the sample mean weight is less than 114 pounds.
ANSWER:
29. Find the probability that the sample mean weight is between 116 and 121 pounds.
ANSWER:
30. Within what limits does the middle 95% of the sampling distribution of sample means for samples of size 16 fall?
ANSWER:
Explanation / Answer
23)
X is a normal distribution with mean 118 and size of sample = 6.8
25)
mean of samples of size 16 is also a normal distribution
26)
mean = 118
standard error = 6.8/sqrt(16) = 1.7
27)
P(X>121) = P(Z > 121 - 118/1.7)
= P(Z > 1.7647)
= 0.0388