WorksheetsAP Stat Test 2
Total questions: 10
Worksheet time: 5mins
In 1965, the mean price of a new car was $2,650 and the standard deviation was $1,000. In 2011, the mean was $30,500 and the standard deviation was $9,000. If a Ford Mustang cost $2,300 in 1965 and $28,000 in 2011, in which year was it more expensive relative to other cars?
1965, because the standardized score is greater than in 2011
In 1965, because the standardized score deviation is smaller
In 2011, because the standardized score is greater than in 1965
2011, because $28,000 is greater than $2,300
We cannot compare the two prices because we don’t know if the prices for each year are Normally distributed
The weights of adult male Labrador Retrievers are approximately Normally distributed with a mean of 87 pounds and a standard deviation of 8 pounds. Which of the following statements is true.
About 95% of adult male Labrador Retrievers weigh between 79 and 95 pounds
Te median weight of adult male Labrador Retrievers is more than 87 pounds
The proportion of adult male Labrador Retrievers that weigh less than 80 pounds is approximately equal to the proportion that weigh more than 94 pounds
Almost all adult male Labrador retrievers weight more than 79 pounds
The standardized weights of 80 pound and 94 pound adult male Labrador Retriers are roughly equal
Which of the following is true about all Normal distributions?
There is no area under the curve for z-scores greater than 3.49
The area underneath the curve is equal to 1
The points at which the curvature changes from up to down (points of inflection) are at the first and third quartile of the distribution
About 68% of the values of the variable are more than one standard deviation away from the mean
The mean is usually greater than the median
The density curve shown takes the value .5 and the interval 0≤x≤2 and takes the value 0 everywhere else. What percent of the observations lie between .5 and 1.2
25%
35%
50%
68%
70%
The 16th percentile in a Normal distribution is 25 and 2.5% of the values in the distribution are greater than 40. Which of the following are the best estimates for the mean and standard deviation of the distribution?
Mean ≈ 32.5; standard deviation ≈ 2.5
Mean ≈ 32.5; standard deviation ≈ 5
Mean ≈ 32.5; standard deviation ≈ 10
Mean ≈30; standard deviation ≈ 2.5
mean ≈ 30; standard deviation ≈ 5
A cumulative relative frequency graph for the 48 racers who finished the grueling 50 km cross-country ski race at the 2010 Vancouver Olympics is given. Approximately what proportion of the racers finished the race in more than 2.15 hours?
.17
.4
.45
.5
.55
The distribution of the time it takes for different people to solve a certain crossword puzzle is skewed to the right, with a mean of 30 minutes and a standard deviation of 15 minutes. The distribution of z-scores for those times is
Normally distributed, with mean 30 and standard deviation 15
Skewed to the right, with mean 30 and standard deviation 15
Normally distibuted, with mean 0 and standard deviation 1
Skewed to the right with mean 0 and standard deviation 1
skewed to the right but the mean and standard deviation cannot be determined without more information
Which of the following is closest to the 61st percentile of the standard Normal distribution?
z = -0.7291
z = -.28
z = .2
z = .28
z = .7291
Here is a Normal probability plot for a set of test scores. What statements is true for the distribution of test scores?
The distribution is Normally distributed
The distributiotn is approximately Normally distributed
The distribution is skewed to the left
The distribution is skewed to the right
There is insufficient information to determine the shape of the distribution
For the density curve shown, which letters correspond to the location of the mean and median of the distribution?
Mean = C, Median = B
Mean = C, Median = C
Mean = A, Median = B
Mean = B, Median = B
Mean = B, Median = A
