The following table describes the results of roadworthiness tests of Ford Focus cars that are three years old (based on data from the Department of Transportation). The random variable x represents the number of cars that failed among six that were tested for roadworthiness. Find the probability of getting three or more cars that fail among six cars tested. x P(x ) 0 0.377 1 0.399 2 0.176 3 0.041 4 0.005 5 0 6 0 Question content area bottom Part 1 A. 0.005 B. 0.222 C. 0.048 D. 0.046

Whether or not you need glasses appears (ha ha) to depend mostly on your genes, but is also influenced by your environment. According to one study, for a family where both parents wear glasses with 5 children, the probability of the children needing glasses is shown below (genetics.thetech.org/ask/ask73). Number of Children with Probability Glasses 0.132 0.330 0.330 0.164 4 0.041 0.003 In a randomly selected family with 5 children, what is the probability that more than 3 children will need glasses?

According to a survey, 30% of college students said that they spend too much time on Facebook. Suppose this result holds true for the current population of all college students. A random sample of six college students is selected. a. Define the random variable X b. X takes on what values?X = ..................................................... c. Determine the number of trials n and the probability of success for this binomial distribution. d.Find the probability that exactly three of these six college students will say that they will spend too much time on Facebook. Round your answer to three decimal places.

Oxygen demand is a term biologists use to describe the oxygen needed by fish and other aquatic organisms for survival. The Environmental Protection Agency conducted a study of a wetland area. In this wetland environment, the mean oxygen demand was u = 9.3 mg/L with 95% of the data ranging from 6.7 mg/L to 11.9 mg/L. Let x be a random variable that represents oxygen demand in this wetland environment. Assume x has a probability distribution that is approximately normal. In USE SALT (a) Use the 95% data range to estimate the standard deviation for oxygen demand. (b) An oxygen demand below 8 indicates that some organisms in the wetland environment may be dying. What is the probability that the oxygen demand will fall below mg/L? (Round your answer to four decimal places.) (c) A high oxygen demand can also indicate trouble. An oxygen demand above 12 may indicate an overabundance of organisms that endanger some types of plant life. What is the probability that the oxygen demand will exceed…

Anyone who has been outdoors on a summer evening has probably heard crickets. Did you know that it is possible to use the cricket as a thermometer? Crickets tend to chirp more frequently as temperatures increase. This phenomenon was studied in detail by George W. Pierce, a physics professor at Harvard. In the following data, x is a random variable representing chirps per second and y is a random variable representing temperature (°F). x 19.8 15.3 20.4 18.1 16.2 15.5 14.7 17.1 y 89.4 73.2 95.3 86.1 78.8 75.2 69.7 82.0 x 15.4 16.2 15.0 17.2 16.0 17.0 14.4 y 69.4 83.3 79.6 82.6 80.6 83.5 76.3           (b) Verify the given sums Σx, Σy, Σx2, Σy2, Σxy, and the value of the sample correlation coefficient r. (Round your value for r to three decimal places.) Σx =   Σy =   Σx2 =   Σy2 =   Σxy =   r =   (c) Find x, and y. Then find the equation of the least-squares line = a + bx. (Round your answers for x and y to two decimal places. Round your answers for a and…

When practicing basketball, Rachel has a 67% chance of making a free throw. She shoots 12 free throws. Let the random variable X be the number of free throws she makes. Find the probability she makes exactly 5 free throws. Give your answer to at least three nonzero decimal places. What is the expected value of X. Interpret this value.

After careful research you observe that the number of hackers active on each day is a random variable Bin(3,0.5) distribution. If no hackers are active, the probability of the website failure is 0.15; If one hacker is active the probability of the website failure is 0.3; if two or more hackers are active the probability of the website failure is 0.5. You conclude that the total probability of website failure on a given day is two decimal place). Assuming there is a failure, the probability no hackers are active is (to (to two decimal places).

The table below displays the results of a study investigating the effectiveness of bicycle safety helmets in preventing head injury. The data consist of a random sample of 793 bicyclists who were involved in bicycle accidents. Head Injury wearing Helmet Yes No Total Yes 17 218 235 No 130 428 558 Total 147 646 793 What is the probability of obtaining a head injury in a bicycle accident? 0.020 0.254 0.185 0.201 0.296

USA Today reported that about 20% of all people In the United States are Illiterate. Suppose you take eleven people at random off a city street. P USE SALT (a) Make a histogram showing the probability distribution of the number of illiterate people out of the eleven people in the sample. 0.30 0.30 0.25 0.25 0.20 0.20 0.15 0.15 0.10 0.10 0.05 0.05 2 3 4 5 7. 8 9 10 11 0 1 2 3 4 5 6 78 9 10 11 0.30 0.30 0.25 0.25 0.20 0.20 0.15 0.15 0.10 0.10 0.05 0.05 0. 0 1 2 3 4 5 6 7 8 9 10 11 0 1 2 3 45 6 7 8 9 10 11 (b) Find the mean and standard deviation of this probability distribution. (Round your standard deviation to two decimal places.) people people Find the expected number of people in this sample who are illiterate. people

A study reported that about 40% of high school students have tried out for a sport at their school. To find out if this applies to Jessica’s school, she surveyed an SRS of 20 students. Nine of them said that they had tried out for a sport. To see if this result is surprising, a simulation is to be conducted to estimate the probability of obtaining a sample result as high as this one. Let 0–3 represent students who tried out for a sport and 4–9 represent students who did not try out for a sport.   Using the line of random numbers to run one simulation, what proportion of students tried out for a sport? 0.40 0.45 0.50 0.60