Overview of Statistics
Descriptive Statistics
Probability
Normal Probability Distributions
Confidence Intervals
100
Determine whether the statement describes a population or a sample. " The high school GPAs of all the parents of your classmates
A) Population B) Sample
A) Population
100
Consider the following data. −5, −5, 14, 14, 14, −5, 15
Determine the mean of the given data
6
100
30. Determine whether the following events are mutually exclusive. “Choosing a heart or a black card out of a standard deck of cards.”
A) Mutually Exclusive B) Not Mutually Exclusive
A) Mutually Exclusive
100
Decide which of the following statements are true. A) There are a limited number of normal distributions. B) The inflection points for any normal distribution are one standard deviation on either side of the mean. C) The x-axis is a horizontal asymptote for all normal distributions. D) The line of symmetry for all normal distributions is x=0.
B) The inflection points of any normal distribution are one standard deviation on either side of the mean
100
Assume all conditions of the Central Limit Theorem are satisfied. What critical value should be used for constructing a 94% confidence interval for the population mean with the population standard deviation unknown. Circle one.
.
Answer= F
200
Determine if the numerical value describes a parameter or a statistic
A recent pole of 3798 corporate executives showed that the average price of their cars is $31,200
A) Population parameter B) Sample Statistic
B Sample Statistic
200
Consider the following data. −5, −5, 14, 14, 14, −5, 15 Step 1. Determine the median of the given data. Answer: _______________
Step 2. Determine if the data set is unimodal, bimodal, multimodal, or has no mode. Identify the
mode(s), if any exist. Answer: __________
Step 1=14
Step 2 = Bimodal
200
Determine whether the following events are mutually exclusive. “Choosing a king or a club out of a standard deck of cards.”
A) Mutually Exclusive B) Not Mutually Exclusive
B) Not Mutually Exclusive
200
Find the area under the standard normal curve to the left of 𝑧 = 1.96. Round your answer to four decimal places, if necessary. Answer: ____________________
Answer= 0.978
200
Given the following confidence interval for a population mean, compute the margin of error, 𝐸. 12.36 < 𝜇 < 12.80 Answer: 𝐸 =_______________
Answer= 0.22
300
Heights of trees are an example of which type of data
A) Discrete B) Continuous C) Neither
B) Continuous
300
Calculate the range, population variance, and population standard deviation for the following data set. If necessary, round to one more decimal place than the largest number of decimal places given in the data.7, 8, 9, 10, 11, 12, 13, 14, 15, 16 Range: _______________
Range 9
300
A box contains 27 red marbles, 33 white marbles, and 85 blue marbles .If a marble is randomly selected from the box, what is the probability that it is red? Express your answer as a simplified fraction or a decimal rounded to four decimal places.
Answer 27/145=0.1862
300
Use the 𝑧-score formula, 𝑧 =
, and the information below to find the mean, 𝜇. Round your answer to one decimal place, if necessary. 𝑧 = 1.75, 𝑥 = 20.3, and 𝜎 = 4.8
Answer = 11.9
300
A professor wants to estimate how many hours per week her student’s study. A simple random sample of 56 students had a mean of 20 hours of studying per week. Construct a 95% confidence interval for the mean number of hours a student studies per week. Assume that the population standard deviation is known to be 2.3 hours per week. Round to two decimal places. Answer: Lower Endpoint: Upper Endpoint:
Ans: Lower Endpoint: 19.4 Upper Endpoint:20.60
400
The number of different colors various boxes of crayons have an example of which type of data?
a) Discrete B) Continuous C) Neither
A) Discrete
400
Calculate the range, population variance, and population standard deviation for the following data set. If necessary, round to one more decimal place than the largest number of decimal places given in the data.7, 8, 9, 10, 11, 12, 13, 14, 15, 16 Population Standard Deviation: _______________
Standard Deviation = 2.9
400
What is the probability of rolling a sum of 9 on a standard pair of six-sided dice? Express your answer as a fraction or a decimal number rounded to three decimal places, if necessary.
Answer: _______________
Answer =1/9= 0.1111
400
The diameters of ball bearings are distributed normally. The mean diameter is 147 millimeters and the standard deviation is 5 millimeters. Find the probability that the diameter of a selected bearing is greater than 138 millimeters. Round your answer to four decimal places.
Answer: ____________________
Answer 0.9641
400
One study claimed that 85% of college students identify themselves as procrastinators. A professor believes that the claim regarding college students is too high. The professor conducts a simple random sample of 164 college students and finds that 132 of them identify themselves as procrastinators. Does this evidence support the professor’s claim that fewer than 85% of college students are procrastinators? Use a 0.10 level of significance. Step A. State the null and alternative hypotheses for the test. Fill in the blank below. 
: 𝑝 = 0.85 
: 𝑝_ 0.85 1)< 2) > 3) ≠ Step B. Compute the value of the test statistic. Round your answer to two decimal places. Answer: ___ C) Interpretation
Ans.
A) <
B)-1.62
C) Reject the null Hypothesis
500
Indicate the level of measurement for the data set described.
Monthly amounts of rain in Seattle over 10 years
A) Interval B) Ratio C) Ordinal D) Nominal
B) Ratio
500
Calculate the range, population variance, and population standard deviation for the following data set. If necessary, round to one more decimal place than the largest number of decimal places given in the data. 7, 8, 9, 10, 11, 12, 13, 14, 15, 16 Population Variance: _______________
Variance = 8.3
500
There are 720 identical plastic chips numbered 1 through 720 in a box.What is the probability of reaching into the box and randomly drawing a chip number that is smaller than 569? Express your answer as a simplified fraction or a decimal rounded to four decimal places.
Answer: _______________
Answer = 71/90 = 0.7889
500
Find the value of 𝑧 such that 0.06 of the area lies to the right of 𝑧. Round your answer to two decimal places. Answer: ____________________
Answer=1.56
500
The following table shows students’ test scores on the first two tests in an introductory physics class. Physics Test Scores First test, x 93 45 61 95 50 42 75 74 80 79 62 91 Second test, y 98 41 56 88 57 59 73 73 83 75 67 94
Step 1. Find an equation of the least-squares regression line. Round your answer to three decimal places, if necessary.
Answer: 
=__+ __𝑥
Step 2. If a student scored an 89 on his first test, make a prediction for his score on the second test. Assume the regression equation is appropriate for prediction. Round your answer to two decimal places, if necessary.
Ans: Answer:
Step 1 =11.496+ 0.857𝑥
Step 2 87.77