Modeling with Exponential and Logarithmic Equations — Unit test Answers

The graph below shows three different normal distributions.Which statement must be true?

The scores of the students on a standardized test are normally distributed, with a mean of 500 and a standard deviation of 110. What is the probability that a randomly selected student has a score between 350 and 550? Use the portion of the standard normal table below to help answer the question.zProbability0.000.50000.250.59870.350.63680.450.67361.000.84131.260.89611.350.91151.360.9131

The mean test scores with standard deviations of four English classes are given below.ClassMeanStandard DeviationMrs. Jones891.9Mrs. Rijo821.4Mr. Phan733.4Mrs. Scott906.1Which statement is most likely to be true?

The histogram below represents the number of points Mandy scored per game. The graph makes the data appear symmetric when it is actually skewed. How can the graph be adjusted to show the skew?

The graph below is used by company 2 to show the average monthly electric cost based on the electricity provider.How could the graph be redrawn so that the difference in monthly electric cost does not appear as great?

The difference between an observational study and an experiment is that

The human resources manager at a company records the length, in hours, of one shift at work, X. He creates the probability distribution below. What is the probability that a worker chosen at random works at least 8 hours?

Dwayne and Alisha both correctly graphed a standard normal curve. Which of the following statements is true?

A high school student volunteers to present a report to the administration about the types of lunches students prefer. He surveys members of his class and records their choices. What type of sampling did the student use?

Which normal distribution has the greatest standard deviation?

The mean game scores and standard deviations of four seasons of a football team are given below.SeasonMeanStandard Deviation2005193.52006212.82007121.0200894.0Which statement must be true?

The table below shows the ages of houses to the nearest year in a neighborhood. Using the age of the houses as the random variable, X, which graph shows the probability distribution, PX(x), of a randomly chosen house?Age of HouseNumber of Houses115220325430

For a standard normal distribution, find the approximate value of . Use the portion of the standard normal table below to help answer the question.zProbability0.000.50000.160.56360.220.58710.780.78231.000.84131.160.87701.780.96252.000.9772

A manager records the number of hours, X, each employee works on his or her shift and develops the probability distribution below. Fifty people work for the manager. How many people work 4 hours per shift?Probability DistributionHours Worked: XProbability: P(X)30.14?50.1460.370.3680.06

The stem-and-leaf plot below shows the number of pages each student in a class read the previous evening.Which statement is true about the data set?

To conduct a survey about the type of phone service most people in Greenville prefer, 10 different blocks in the neighborhood are chosen. On these 10 blocks, 10 houses are selected at random, and then each resident of each of those houses is interviewed. This type of sampling method is

Which of the following is a valid probability distribution?

A convenience sample differs from a voluntary sample in that

The hourly wages earned by 20 employees are shown in the first box-and-whisker plot below. The person earning $15 per hour quits and is replaced with a person earning $8 per hour. The graph of the resulting salaries is shown in plot 2.Plot 1 Plot 2 How does the mean and median change from plot 1 to plot 2?

The lengths of a particular snake are approximately normally distributed with a given mean = 15 in. and standard deviation = 0.8 in. What percentage of the snakes are longer than 16.6 in.?