MATH 1342 McLennan CC Week 6 Mean and Standard Deviation Exam Practice
What's wrong with the following statement?"Because the digits 0, 1, 2, . . . , 9 are the normal results from lottery drawings, such randomly selected numbers have a normal distribution."Choose the correct answer below.A.The lottery digits have a normal distribution only if the digits are drawn with replacement, which is not specified.B.It is not the randomly selected digits that have a normal distribution but rather the chances of winning the lottery.C.The lottery digits have a normal distribution only if the digits are drawn without replacement, which is not specified.D.Since the probability of each digit being selected is equal, lottery digits have a uniform distribution, not a normal distribution.What requirements are necessary for a normal probability distribution to be a standard normal probability distribution?Choose the correct answer below.A.The mean and standard deviation have the values of mu equals 1μ=1 and sigma equals 0.σ=0.B.The mean and standard deviation have the values of mu equals 1μ=1 and sigma equals 1.σ=1.C.The mean and standard deviation have the values of mu equals 0μ=0 and sigma equals 0.σ=0.D.The mean and standard deviation have the values of mu equals 0μ=0 and sigma equals 1.σ=1.The expression z Subscript alphazα denotes the z score with an area of alphaα ▼between minus z Subscript alpha Baseline and z Subscript alpha Baseline .between −zα and zα.to its right.to its right.to its left.Find the area of the shaded region. The graph depicts the standard normal distribution with mean 0 and standard deviation 1.Click to view page 1 of the table.LOADING... Click to view page 2 of the table.LOADING...z equals 0.83z=0.83A graph with a bell-shaped curve, divided into 2 regions by a line from top to bottom on the right side. The region left of the line is shaded. The z-axis below the line is labeled "z=0.83".The area of the shaded region is nothing.(Round to four decimal places as needed.)Find the area of the shaded region. The graph depicts the standard normal distribution of bone density scores with mean 0 and standard deviation 1.z= -0.99A symmetric bell-shaped curve is plotted over a horizontal scale. A vertical line runs from the scale to the curve at labeled coordinate “z equals negative 0.99,” which is to the left of the curve’s center and peak. The area under the curve to the right of the vertical line is shaded.The area of the shaded region is nothing.(Round to four decimal places as needed.)Find the area of the shaded region. The graph depicts the standard normal distribution of bone density scores with mean 0 and standard deviation 1.font size decreased by 2 z equals negative 0.96z=−0.96font size decreased by 2 z equals 1.23z=1.23A symmetric bell-shaped curve is plotted over a horizontal scale. Two vertical lines run from the scale to the curve at labeled coordinates “z equals negative 0.96,” which is to the left of the curve’s center and peak, and “z equals 1.23,” which is to the right of the curve’s center and peak. The area under the curve between the vertical lines is shaded.The area of the shaded region is nothing.(Round to four decimal places as needed.)Find the indicated z score. The graph depicts the standard normal distribution with mean 0 and standard deviation 1.Click to view page 1 of the table.LOADING... Click to view page 2 of the table.LOADING... zz0.95250.9525A graph with a bell-shaped curve, divided into 2 regions by a line from top to bottom on the right side. The region left of the line is shaded and is labeled 0.9525.The indicated z score is nothing.(Round to two decimal places as needed.)Find the indicated z score. The graph depicts the standard normal distribution with mean 0 and standard deviation 1. zz0.26110.26110A symmetric bell-shaped curve is plotted over a horizontal scale with two labeled coordinates. One coordinate is labeled "0" and is located at the center and peak of the curve. The other coordinate is labeled "z," and is to the left of 0. A vertical line extends from the scale to the curve at z. The area under the curve to the left of z is shaded and labeled “0.2611.”The indicated z score is nothing.(Round to two decimal places as needed.)Find the indicated z score. The graph depicts the standard normal distribution with mean 0 and standard deviation 1. zz0.87490.87490A symmetric bell-shaped curve is plotted over a horizontal scale with two labeled coordinates. One coordinate is labeled "0" and is located at the center and peak of the curve. The other coordinate is labeled "z," and is to the left of 0. A vertical line extends from the scale to the curve at z. The area under the curve to the right of z is shaded and labeled “0.8749.”The indicated z score is nothing.(Round to two decimal places as needed.)Assume that a randomly selected subject is given a bone density test. Those test scores are normally distributed with a mean of 0 and a standard deviation of 1. Find the probability that a given score is less than negative 0.51−0.51 and draw a sketch of the region.Sketch the region. Choose the correct graph below.A.-0.51A symmetric bell-shaped curve is plotted over a horizontal scale. A vertical line runs from the scale to the curve at labeled coordinate negative 0.51, which is to the left of the curve’s center and peak. The area under the curve to the right of the vertical line is shaded.B.-0.51A symmetric bell-shaped curve is plotted over a horizontal scale. A vertical line runs from the scale to the curve at labeled coordinate negative 0.51, which is to the left of the curve’s center and peak. The area under the curve to the left of the vertical line is shaded.C.0.51A symmetric bell-shaped curve is plotted over a horizontal scale. A vertical line runs from the scale to the curve at labeled coordinate 0.51, which is to the right of the curve’s center and peak. The area under the curve to the left of the vertical line is shaded.D.Assume that a randomly selected subject is given a bone density test. Those test scores are normally distributed with a mean of 0 and a standard deviation of 1. Draw a graph and find the probability of a bone density test score greater than 0.820.82.Sketch the region. Choose the correct graph below.A.0.82A symmetric bell-shaped curve is plotted over a horizontal axis. A vertical line segment runs from the horizontal axis to the curve at labeled coordinate 0.82, which is to the right of the curve’s center and peak. The area under the curve to the right of 0.82 is shaded.B.-0.82A symmetric bell-shaped curve is plotted over a horizontal axis. A vertical line segment runs from the horizontal axis to the curve at labeled coordinate negative 0.82, which is to the left of the curve’s center and peak. The area under the curve to the left of negative 0.82 is shaded.C.-0.820.82Assume that thermometer readings are normally distributed with a mean of 0degrees°C 1.00degrees°C. Between 0.750.75 Click to view page 1 of the table.LOADING...LOADING...Draw a sketch. Choose the correct graph below.A symmetric bell-shaped curve is plotted over a horizontal axis. Two vertical line segments run from the horizontal axis to the curve and are equidistant from the center and peak of the curve. One vertical line is at the labeled coordinate negative 0.82, which is to the left of the curve's center and peak. The other vertical line is at the labeled coordinate 0.82, which is to the right of the curve's center and peak. The area under the curve between negative 0.82 and 0.82 is shaded.D.and a standard deviation of A thermometer is randomly selected and tested. For the case below, draw a sketch, and find the probability of the reading. (The given values are in Celsius degrees.)and 2.252.25 Click to view page 2 of the table.A.z=0.75z=2.25A graph with a bell-shaped curve, divided into 3 regions by 2 lines from top to bottom, both on the right side. Moving from left to right, the region right of the second line is shaded. The z-axis below this line is labeled "z=2.25". The z-axis below the first line is labeled "z=0.75".B.z=0.75z=2.25A graph with a bell-shaped curve, divided into 3 regions by 2 lines from top to bottom, both on the right side. Moving from left to right, the region left of the first line is shaded. The z-axis below this line is labeled "z=0.75". The z-axis below the second line is labeled "z=2.25".C.z=0.75Find the indicated critical value.z 0.10z0.10Click to view page 1 of the table.LOADING...LOADING...z 0.10z0.10equals=nothing(Round to twotwo ind the indicated area under the curve of the standard normal distribution; then convert it to a percentage and fill in the blank.About ______% of the area is between zequals=minus−1 zequals=1 About nothing% zequals=minus−1 zequals=1 Find the indicated area under the curve of the standard normal distribution; then convert it to a percentage and fill in the blank.About ______% of the area is between zequals=minus−2 zequals=2 About nothing% zequals=minus−2 zequals=2 Find the indicated area under the curve of the standard normal distribution; then convert it to a percentage and fill in the blank.About ______% of the area is between zequals=minus−3 zequals=3 About nothing% zequals=minus−3 zequals=3 Click to view page 2 of the table.decimal places asand (or within 1 standard deviation of the mean).of the area is between and (or within 1 standard deviation of the mean).and (or within 2 standard deviations of the mean).of the area is between and (or within 2 standard deviations of the mean).and (or within 3 standard deviations of the mean).of the area is between and (or within 3 standard deviations of the mean).(Round(Round(Round0.51Which of the following is NOT a descriptor of a normal distribution of a random variable?Choose the correct answer below.The graph of the distribution is bell-shaped.The graph is centered around 0.The graph is centered around the mean.Fill in the blank.A continuous random variable has a _______ distribution if its values are spread evenly over the range of possibilities.A continuous random variable has a ▼PoissonnormaluniformbinomialWhich of the following is NOT a requirement for a density curve?Choose the correct answer below.The graph is centered around 0.Every point on the curve must have a vertical height that is 0 or greater.The total area under the curve must equal 1.Fill in the blank.Finding probabilities associated with distributions that are standard normal distributions is equivalent to _______.Finding probabilities associated with distributions that are standard normal distributions is equivalent to ▼finding the variance of the distribution.finding the z-scores associated with the probabilities.finding the area of the shaded region representing that probability.A.B.C.D. A.B.C.D.-0.51