Ch. 8 Sampling Distributions
8.1 Distribution of the Sample Mean
1 Understand the Concept of a Sampling Distribution
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.
1) The ages of five randomly chose cars in the parking lot are determined to be 7, 9, 3,4, and 6 years old. If we
consider this sample of 5 in groups of 3, how many groups can be formed?
A) 10
B) 5
C) 30
D) 60
2) The ages of five randomly chosen cars in the parking lot are determined to be 7, 9, 3, 4, and 6 years old. If we
consider this sample of 5 in groups of 3, what is the probability of selecting a group that has an average age of
6
2
3
years?
A) 1/10
B) 2/10
C) 3/10
D) 4/10
3) The ages of five randomly chosen cars in the parking lot are determined to be 7, 9, 3, 4, and 6 years old. If we
consider this sample of 5 in groups of 3, what is the probability of the true mean falling between 5.5 and 6.5
years?
A) 0.5
B) 0.4
C) 0.55
D) 0.6
4) The ages of five randomly chosen cars in the parking lot are determined to be 7, 9, 3, 4, and 6 years old. If we
consider this sample of 5 in groups of 3, what is the probability of the true mean being more than 6 years?
A) 0.4
B) 0.5
C) 0.1
D) 0.6
5) John has six bills of paper money in the following denominations: $1, $5, $10, $20, $50, and $100 If he selects 3
bills at a time how many, how many groups can be formed?
A) 20
B) 10
C) 30
D) 15
6) John has six bills of paper money in the following denominations: $1, $5, $10, $20, $50, and $100 If he selects 3
bills at a time what is the probability of selecting a group that has an average value of at least $26?
A) 0.55
B) 0.50
C) 0.60
D) 0.45
7) John has six bills of paper money in the following denominations: $1, $5, $10, $20, $50, and $100 If he selects 3
bills at a time what is the probability of selecting a group that has an average value of between $40 and $45?
A) 0.15
B) 0.05
C) 0.25
D) 0.20
8) John has six bills of paper money in the following denominations: $1, $5, $10, $20, $50, and $100 If he selects 3
bills at a time what is the probability of selecting a group that has an average value of equal to or less than $25?
A) 0.45
B) 0.86
C) 0.50
D) 0.35
Page 206