1 of 40 A class consists of 50 women and 82 men. If a student is randomly selected, what is the probability that the student is a woman? 2.5 Points A. 32/132 B. 27/66 C. 50/132 D. 82/132 If a person is randomly selected, find the probability that his or her birthday is not in May. Ignore leap years. There are 365 days in a year. Express your answer as a fraction. A. 335/365 B. 334/365 C. 336/365 D. 30/365 2.5 Points Question 3 of 40 A bag contains 4 red marbles, 3 blue marbles, and 7 green marbles. If a marble is randomly selected from the bag, what is the probability that it is blue? A. 2/11 B. 3/11 C. 5/14 D. 3/14 2.5 Points Question 4 of 40 Of 1308 people who came into a blood bank to give blood, 314 people had high blood pressure. Estimate the probability that the next person who comes in to give blood will have high blood pressure (to 3 decimal places). A. 0.250 B. 0.490 C. 0.240 D. 0.160 Question 5 of 40 A study of 600 college students taking Statistics 101 revealed that 54 students received the grade of A. Typically 10% of the class gets an A. The difference between this group of students and the expected value is not significant at the 0.05 level. What does this mean in this case? A. The probability that the difference occurred due to chance is less than 0.05. B. The probability of getting an A is 10% and only 9% got an A in this study. The difference is less than 5% so it is not significant. C. There is not enough information to make any conclusion. D. The probability that the difference occurred due to chance is more than 0.05. 2.5 Points 2.5 Points Question 6 of 40 In a poll, respondents were asked whether they had ever been in a car accident. 220 respondents indicated that they had been in a car accident and 370 respondents said that they had not been in a car accident. If one of these respondents is randomly selected, what is the probability of getting someone who has been in a car accident? Round to the nearest thousandth. A. 0.384 B. 0.380 C. 0.373 D. 0.370 2.5 Points Question 7 of 40 The probability that Luis will pass his statistics test is 0.94. Find the probability that he will fail his statistics test. A. 0.02 B. 0.05 C. 0.94 D. 0.06 If you flip a coin three times, the possible outcomes are HHH, HHT, HTH, HTT, THH, THT, TTH, TTT. What is the probability of getting at least two tails? A. 1/2 B. 2/3 C. 3/4 D. 4/9 2.5 Points Question 9 of 40 Suppose you buy 1 ticket for $1 out of a lottery of 1000 tickets where the prize for the one winning ticket is to be $500. What is your expected value? A. $0.00 B. $0.40 C. $1.00 D. $0.50 Reset Selection 2.5 Points Question 10 of 40 If you flip a coin three times, the possible outcomes are HHH, HHT, HTH, HTT, THH, THT, TTH, TTT. What is the probability that at least two heads occur consecutively? A. 1/8 B. 3/8 C. 5/8 D. 6/8 2.5 Points uestion 11 of 40 Suppose you have an extremely unfair die: The probability of a 6 is 3/8, and the probability of each other number is 1/8. If you toss the die 32 times, how many twos do you expect to see? A. 2 B. 4 C. 3 D. 5 2.5 Points Question 12 of 40 Suppose you have an extremely unfair coin: the probability of a head is 1/5, and the probability of a tail is 4/5. If you toss the coin 40 times, how many heads do you expect to see? A. 8 B. 6 C. 5 D. 4 Question 13 of 40 2.5 Points The data set represents the income levels of the members of a country club. Estimate the probability that a randomly selected member earns at least $98,000. 112,000 126,000 90,000 133,000 94,000 112,000 98,000 82,000 147,000 182,000 86,000 105,000 140,000 94,000 126,000 119,000 98,000 154,000 78,000 119,000 A. 0.4 B. 0.6 C. 0.66 D. 0.7 Question 14 of 40 2.5 Points Sammy and Sally each carry a bag containing a banana, a chocolate bar, and a licorice stick. Simultaneously, they take out a single food item and consume it. The possible pairs of food items that Sally and Sammy consumed are as follows. chocolate bar - chocolate bar licorice stick - chocolate bar banana - banana chocolate bar - licorice stick licorice stick - licorice stick chocolate bar - banana banana - licorice stick licorice stick - banana banana - chocolate bar Find the probability that no chocolate bar was eaten. A. 4/9 B. 5/9 C. 7/9 D. 5/8 2.5 Points Question 15 of 40 On a multiple choice test, each question has 6 possible answers. If you make a random guess on the first question, what is the probability that you are correct? A. 1/5 B. 1/6 C. 1/4 D. 2/5 2.5 Points Question 16 of 40 Based on meteorological records, the probability that it will snow in a certain town on January 1st is 0.413. Find the probability that in a given year it will not snow on January 1st in that town. A. 0.345 B. 0.425 C. 0.587 D. 0.592 2.5 Points Question 17 of 40 A 28-year-old man pays $125 for a one-year life insurance policy with coverage of $140,000. If the probability that he will live through the year is 0.9994, to the nearest dollar, what is the man's expected value for the insurance policy? A. $139,916 B. $41 C. $84 D. $124 Question 18 of 40 If you flip a coin three times, the possible outcomes are HHH, HHT, HTH, HTT, THH, THT, TTH, TTT. What is the probability of getting at least one head? 2.5 Points A. 4/9 B. 5/6 C. 7/8 D. 5/8 2.5 Points Question 19 of 40 A sample space consists of 46 separate events that are equally likely. What is the probability of each? A. 1/24 B. 1/46 C. 1/32 D. 1/18 2.5 Points Question 20 of 40 Suppose you have an extremely unfair coin: the probability of a head is 1/3 and the probability of a tail is 2/3. If you toss the coin 72 times, how many heads do you expect to see? A. 12 B. 22 C. 24 D. 26 Question 21 of 40 2.5 Points Eleven female college students are selected at random and asked their heights. The heights (in inches) are as follows: 67, 59, 64, 69, 65, 65, 66, 64, 62, 64, 62 Estimate the mean height of all female students at this college. Round your answer to the nearest tenth of an inch if necessary. A. It is not possible to estimate the population mean from this sample data B. 64.3 inches C. 64.9 inches D. 63.7 inches 2.5 Points Question 22 of 40 Monthly incomes of employees at a particular company have a mean of $5954. The distribution of sample means for samples of size 70 is normal with a mean of $5954 and a standard deviation of $259. Suppose you take a sample of size 70 employees from the company and find that their mean monthly income is $5747. How many standard deviations is the sample mean from the mean of the sampling distribution? A. 0.8 standard deviations above the mean B. 0.8 standard deviations below the mean C. 7.3 standard deviations below the mean D. 207 standard deviations below the mean Question 23 of 40 2.5 Points Which graph has two groups of data, correlations within each group, but no correlation among all the data? A. B. C. D. Question 24 of 40 2.5 Points The scatter plot and best-fit line show the relation between the price per item (y) and the availability of that item (x) in arbitrary units. The correlation coefficient is -0.95. Determine the amount of variation in pricing explained by the variation in availability. A. 5% B. 10% C. 95% D. 90% Question 26 of 40 Which line of the three shown in the scatter diagram below fits the data best? A. A B. B 2.5 Points C. C D. All the lines are equally good 2.5 Points Question 27 of 40 In a poll of 400 voters in a certain state, 61% said that they opposed a voter ID bill that might hinder some legitimate voters from voting. The margin of error in the poll was reported as 4 percentage points (with a 95% degree of confidence). Which statement is correct? A. The reported margin of error is consistent with the sample size. B. There is not enough information to determine whether the margin of error is consistent with the sample size. C. The sample size is too small to achieve the stated margin of error. D. For the given sample size, the margin of error should be smaller than stated. Question 28 of 40 Which point below would be an outlier if it were on the following graph? A. (25, 20) B. (5, 12) 2.5 Points C. (7, 5) D. (5, 3) Question 29 of 40 2.5 Points Select the best fit line on the scatter diagram below. A. A B. B C. C D. None of the lines is the line of best fit Question 30 of 40 2.5 Points The graph shows a measure of fitness (y) and miles walked weekly. Identify the probable cause of the correlation. A. The correlation is coincidental. B. There is a common underlying cause of the correlation. C. There is no correlation between the variables. D. Walking is a direct cause of the fitness 2.5 Points Question 31 of 40 A researcher wishes to estimate the proportion of college students who cheat on exams. A poll of 490 college students showed that 33% of them had, or intended to, cheat on examinations. Find the margin of error for the 95% confidence interval. A. 0.0432 B. 0.0434 C. 0.0425 D. 0.0427 Question 32 of 40 Select the best estimate of the correlation coefficient for the data depicted in the scatter diagram. 2.5 Points A. 0.60 B. -0.97 C. 0.10 D. -0.60 2.5 Points Question 33 of 40 A sample of 64 statistics students at a small college had a mean mathematics ACT score of 28 with a standard deviation of 4. Estimate the mean mathematics ACT score for all statistics students at this college. Give the 95% confidence interval. A. 28.0 to 30.0 B. 25.0 to 27.0 C. 29.0 to 31.0 D. 27.0 to 29.0 2.5 Points Question 34 of 40 Of the 6796 students in one school district, 1537 cannot read up to grade level. Among a sample of 812 of the students from this school district, 211 cannot read up to grade level. Find the sample proportion of students who cannot read up to grade level. A. 0.14 B. 0.26 C. 211 D. 0.23 2.5 Points Question 35 of 40 30% of the fifth grade students in a large school district read below grade level. The distribution of sample proportions of samples of 100 students from this population is normal with a mean of 0.30 and a standard deviation of 0.045. Suppose that you select a sample of 100 fifth grade students from this district and find that the proportion that reads below grade level in the sample is 0.36. What is the probability that a second sample would be selected with a proportion less than 0.36? A. 0.8932 B. 0.8920 C. 0.9032 D. 0.9048 Question 36 of 40 Select the best estimate of the correlation coefficient for the data depicted in the scatter diagram. 2.5 Points A. -0.9 B. 0.1 C. 0.5 D. 0.9 Question 37 of 40 Write possible coordinates for the single outlier such that it would no longer be an outlier. A. (23, 18) B. (20, 5) 2.5 Points C. (15, 15) D. (12, 15) 2.5 Points Question 38 of 40 A researcher wishes to estimate the proportion of college students who cheat on exams. A poll of 560 college students showed that 27% of them had, or intended to, cheat on examinations. Find the 95% confidence interval. A. 0.2323 to 0.3075 B. 0.2325 to 0.3075 C. 0.2325 to 0.3185 D. 0.2323 to 0.3185 Question 39 of 40 2.5 Points The scatter plot and best-fit line show the relation among the data for the price of a stock (y) and employment (x) in arbitrary units. The correlation coefficient is 0.8. Predict the stock price for an employment value of 6. A. 8.8 B. 6.2 C. 8.2 D. None of the values are correct 2.5 Points Question 40 of 40 A researcher wishes to estimate the mean amount of money spent per month on food by households in a certain neighborhood. She desires a margin of error of $30. Past studies suggest that a population standard deviation of $248 is reasonable. Estimate the minimum sample size needed to estimate the population mean with the stated accuracy. A. 274 B. 284 C. 264 D. 272