Questions Asnwers Linear Algebra

10/29/2018 Print Test a) 0.54 b) 0.12 c) 0.58 d) 0.70 e) 0.51 f) None of the above. Question 4 Given the following sampling distribution: X -17 -12 2 11 15 P(X) 7⁄100 1⁄20 1⁄100 3⁄50 ___ What is P(X = 15)? a) 0.82 b) 0.81 c) 0.80 d) 0.15 e) 0.79 f) None of the above Question 5 Given the following sampling distribution: X -16 -11 -3 11 16 P(X) 1⁄20 3⁄100 1⁄20 9⁄100 ___ What is P(X > -11)? a) 0.95 b) 0.92 c) 0.94 2/6 10/29/2018 Print Test d) 0.90 e) 0.91 f) None of the above Question 6 Given the following sampling distribution: X -18 -10 -4 11 15 P(X) 3⁄100 3⁄100 9⁄100 3⁄100 ___ What is the mean of this sampling distribution? a) -1.2 b) 11.2 c) 11.4 d) 11.1 e) -0.4 f) None of the above Question 7 Suppose you have a distribution, X, with mean = 13 and standard deviation = 3. Define a new random variable Y = 4X - 5. Find the mean and standard deviation of Y. a) E[Y] = 47; σY = 7 b) E[Y] = 47; σY = 48 c) E[Y] = 47; σY = 12 d) E[Y] = 52; σY = 7 e) E[Y] = 52; σY = 48 f) None of the above Question 8 In testing a certain kind of missile, target accuracy is measured by the average distance X (from the target) at which the missile explodes. The distance X is measured in miles and the sampling distribution of X is given 3/6 10/29/2018 Print Test by: X 0 10 50 100 P(X) 1⁄14 1⁄7 2⁄7 1⁄2 Calculate the mean of this sampling distribution. a) 37.6 b) 64.2 c) 65.7 d) 1410.2 e) 67.2 f) None of the above Question 9 In testing a certain kind of missile, target accuracy is measured by the average distance X (from the target) at which the missile explodes. The distance X is measured in miles and the sampling distribution of X is given by: X 0 10 50 100 P(X) 1⁄32 1⁄16 1⁄8 25⁄32 Calculate the variance of this sampling distribution. a) 906.3 b) 302.1 c) 85.0 d) 30.1 e) 4766.7 f) None of the above Question 10 Suppose you want to play a carnival game that costs 5 dollars each time you play. If you win, you get $100. The probability of winning is 3⁄100. What is the expected value of the amount the carnival stands to gain? a) 2.00 4/6 10/29/2018 Print Test b) 3.00 c) 2.20 d) 2.30 e) -2.00 f) None of the above Question 11 Suppose you want to play a carnival game that costs 5 dollars each time you play. If you win, you get $100. The probability of winning is 3⁄100. What is the expected value of the amount that you, the player, stand to gain? a) -1.90 b) -3.00 c) -2.10 d) -2.00 e) 2.00 f) None of the above Question 12 A random sample of 2 measurements is taken from the following population of values: -1, 0, 2, 3, 6. What is the probability that the range of the sample is 3? a) 0.1 b) 0.6 c) 0.3 d) 0.5 e) 0.4 f) None of the above Question 13 A furniture store is having a sale on sofas and you're going to buy one. The advertisers know that buyers get to the store and that 1 out of 11 buyers change to a more expensive sofa than the one in the sale 5/6 10/29/2018 Print Test advertisement. Let X be the cost of the sofa. What is the average cost of a sofa if the advertised sofa is $100 and the more expensive sofa is $375? a) 237.50 b) 124.89 c) 350.00 d) 122.92 e) 125.00 f) None of the above 6/6 10/29/2018 Print Test PRINTABLE VERSION Quiz 4 Question 1 Suppose you have a distribution, X, with mean = 9 and standard deviation = 5. Define a new random variable Y = 8X - 4. Find the mean and standard deviation of Y. a) E[Y] = 68; σY = 40 b) E[Y] = 72; σY = 320 c) E[Y] = 72; σY = 36 d) E[Y] = 68; σY = 36 e) E[Y] = 68; σY = 320 f) None of the above Question 2 Which statement is not true for a binomial distribution with n = 10 and p = 1/20 ? a) The highest probability occurs when x equals 0.5000 b) The probability that x equals 1 is 0.3151 c) The number of trials is equal to 10 d) The mean equals 0.5000 e) The standard deviation is 0.6892 f) None of the above Question 3 In testing a new drug, researchers found that 3% of all patients using it will have a mild side effect. A random sample of 5 patients using the drug is selected. Find the probability that none will have this mild side effect. a) 0.8587 b) 0.0300 c) 0.1413 1/6 10/29/2018 Print Test d) 0.9700 e) 0.5589 f) None of the above Question 4 In testing a new drug, researchers found that 6% of all patients using it will have a mild side effect. A random sample of 12 patients using the drug is selected. Find the probability that at least one will have this mild side effect. a) 0.9400 b) 0.0600 c) 0.3292 d) 0.5241 e) 0.6605 f) None of the above Question 5 In testing a new drug, researchers found that 2% of all patients using it will have a mild side effect. A random sample of 15 patients using the drug is selected. Find the probability that exactly two will have this mild side effect. a) 0.03230 b) 0.04230 c) 0.08230 d) 0.05230 e) 0.07230 f) None of the above Question 6 A manufacturer of matches randomly and independently puts 15 matches in each box of matches produced. The company knows that one-tenth of 9 percent of the matches are flawed. What is the probability that a matchbox will have one or fewer matches with a flaw? a) 0.007930 2/6 10/29/2018 Print Test b) 0.9921 c) 0.9910 d) 0.1190 e) 0.8732 f) None of the above Question 7 Suppose you have a binomial distribution with n = 15 and p = 0.8. Find P(9 ≤ X ≤ 11). a) 0.3777 b) 0.2461 c) 0.3337 d) 0.1461 e) 0.5337 f) None of the above Question 8 Each year a company selects a number of employees for a management training program. On average, 30 percent of those sent complete the program. Out of the 21 people sent, what is the probability that exactly 4 complete the program? a) 0.1983 b) 0.1127 c) 0.2983 d) 0.3127 e) 0.1567 f) None of the above Question 9 Each year a company selects a number of employees for a management training program. On average, 40 percent of those sent complete the program. Out of the 41 people sent, what is the probability that 12 or more complete the program? 3/6 10/29/2018 Print Test a) 0.8945 b) 0.1054 c) 0.2054 d) 0.0566 e) 0.9433 f) None of the above Question 10 A fish tank in a pet store has 21 fish in it. 10 are orange and 11 are white. Determine the probability that if we select 4 fish from the tank, at least 2 will be white. a) 0.7443 b) 0.9643 c) 0.2556 d) 0.2776 e) 0.5238 f) None of the above Question 11 Identify the following distribution as binomial, geometric or neither. There is a probability of 0.08 that a vaccine will cause a certain side effect. Suppose that a number of patients are inoculated with the vaccine. We are interested in the number of patients vaccinated until the first side effect is observed. a) Geometric b) Binomial c) Neither Question 12 A quarter back completes 20% of his passes. We want to observe this quarterback during one game to see how many pass attempts he makes before completing one pass. What is the probability that the quarterback throws 4 incomplete passes before he has a completion? a) 0.0875 4/6 10/29/2018 Print Test b) 0.0819 c) 0.9180 d) 0.9344 e) 0.0655 f) None of the above Question 13 A quarter back completes 30% of his passes. We want to observe this quarterback during one game to see how many pass attempts he makes before completing one pass. Determine the probability that it takes more than 12 attempts before he completes a pass. a) 0.0138 b) 0.0041 c) 0.9861 d) 0.9958 e) 0.0261 f) None of the above Question 14 Joe has an 28% probability of passing his statistics quiz 4 each time he takes it. What is the probability he will take no more than 6 tries to pass it? a) 0.0390 b) 0.1393 c) 0.0610 d) 0.9609 e) 0.8606 f) None of the above Question 15 Joe has an 10% probability of passing his statistics quiz 4 each time he takes it. How many times should Joe expect to take his quiz before passing it? 5/6 10/29/2018 Print Test a) 21 b) 12 c) 9 d) 10 e) 70 f) None of the above 6/6