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A consignment of 12 refurbished laptops contains 3 defective units. If 4 laptops are randomly selected for inspection, what is the probability that at least 2 of them will be defective? A. 0. B. 0. C. 0. D. 0. ANSWER: A. Research shows that outbreak of a new virus is causing fatalities in 3 out of every 10 patients affected by the virus. If 12 patients are admitted in the hospital affected with virus, calculate the probability that all patients will survive. A. 0. B. 0. C. 0. D. 0. ANSWER: A. Research shows that outbreak of a new virus is causing fatalities in 3 out of every 10 patients affected by the virus. If 12 patients are admitted in the hospital affected with virus, calculate the probability that at least 10 patients will survive. A. 0. B. 0. C. 0. D. 0. ANSWER: A. Research shows that outbreak of a new virus is causing fatalities in 3 out of every 10 patients affected by the virus. If 12 patients are admitted in the hospital affected with virus, calculate the probability that at most 10 patients will survive. A. 0. B. 0. C. 0. D. 0. ANSWER: A. The life of a light bulb is normally distributed with standard deviation of 100 hours. The probability that the life of a bulb selected at random would exceed 3,200 hours is 0.0228. What is the probability that the life of a light bulb selected at random would not be less than 2,800 hours? A. 0. B. 0. C. 0. D. 0. ANSWER: A. Inaam is going to play a series of 3 tennis matches with Misbah. Assuming that the chances of winning or losing are equal, find the probability of Two wins and One loss. A. 0. B. 0. C. 0. D. 0. ANSWER: A. Inaam is going to play a series of 3 tennis matches with Misbah. Assuming that the chances of winning or losing are equal, find the probability of At Least Two WIns. A. 0. B. 0. C. 0.
D. 0.
ANSWER: A.
Inaam is going to play a series of 3 tennis matches with Misbah. Assuming that the chances of winning or losing are equal, find the probability of No Loss. A. 0. B. 0. C. 0. D. 0. ANSWER: A. Inaam is going to play a series of 3 tennis matches with Misbah. Assuming that the chances of winning or losing are equal, find the probability of At Most Two Wins. A. 0. B. 0. C. 0. D. 0. ANSWER: A. APZ Limited manufactures a component having a diameter of 3.0 cm. a customer has ordered 100,000 units and has indicated that he would be willing to accept a variation of up to 0. cm. the diameter of component has normal distribution with mean of 3.0 cm. and standard deviation = 0.005 cm. Estimate the number of components that the customer would reject. A. 4560 B. 4650 C. 4056 D. 5460 ANSWER: A. Small Insurance Company receives an average of 8 insurance claims daily during the month of Ramadan every year. Using Poisson Distribution, find the probability that on a certain day in Ramadan, the company will receive No Claim. A. 0. B. 0. C. 0. D. 0. ANSWER: A. Small Insurance Company receives an average of 8 insurance claims daily during the month of Ramadan every year. Using Poisson Distribution, find the probability that on a certain day in Ramadan, the company will receive Less than four insurance claims. A. 0. B. 0. C. 0. D. 0. ANSWER: A. Small Insurance Company receives an average of 8 insurance claims daily during the month of Ramadan every year. Using Poisson Distribution, find the probability that on a certain day in Ramadan, the company will receive At least two insurance claims. A. 0. B. 0. C. 0. D. 0. ANSWER: A. A multiple choice examination consists of ten questions and each question is followed by four choices. A student will pass the exam if he answers five questions correctly. Assuming
ANSWER: A.
A bag contains four red balls, three green balls, one blue ball and one yellow ball. Two balls are drawn out from the bag at random, without replacement. Find the probability that Both the balls are of the same color A. 0. B. 0. C. 0. D. 0. ANSWER: A. A bag contains four red balls, three green balls, one blue ball and one yellow ball. Two balls are drawn out from the bag at random, without replacement. Find the probability that Both the balls are of different color A. 0. B. 0. C. 0. D. 0. ANSWER: A. A bag contains four red balls, three green balls, one blue ball and one yellow ball. Two balls are drawn out from the bag at random, without replacement. Find the probability that At Least One Ball is Green. A. 21/ B. 20/ C. 15/ D. 25/ ANSWER: A. A box contains 10 items out of which 3 are defective. If four items are selected at random, without replacement, find the probability that at least 2 are defective. A. 0. B. 0. C. 0. D. 0. ANSWER: A. In a T-20 Cricket Match between Falcon Club (FC) and Eagle Club (EC), the probability tow in by FC is 0.4. in a series of five T-20 matches, find the probability that FC would win Exactly Two Matches. A. 0. B. 0. C. 0. D. 0. ANSWER: A. In a T-20 Cricket Match between Falcon Club (FC) and Eagle Club (EC), the probability tow in by FC is 0.4. in a series of five T-20 matches, find the probability that FC would winAt Least Two Matches. A. 0. B. 0. C. 0. D. 0. ANSWER: A. In a T-20 Cricket Match between Falcon Club (FC) and Eagle Club (EC), the probability tow in by FC is 0.4. in a series of five T-20 matches, find the probability that FC would win Less than Four Matches. A. 0.
B. 0.
C. 0.
D. 0.
ANSWER: A.
A problem of mathematics is given to three students A, B and C. Their respective probability of solving is 1/2, 1/3, and 1/4. Find the probability that at least two of them will solve the problem. A. 7/ B. 1/ C. 5/ D. 1/ ANSWER: A. There are six positive and eight negative numbers. Four numbers are chosen at random and multiplied. What is the probability that the product is a positive number? A. 505/1001 OR 0. B. 500/1001 OR 0. C. 550/1001 OR 0549451 D. None of these ANSWER: A. Out of every 4,000 shirts made in a garment factory, 22 are defective. Using Poisson distribution, find that a sample of 300 shirts contain More than 3 defective shirts. A. 0. B. 0. C. 0. D. 0. ANSWER: A. Out of every 4,000 shirts made in a garment factory, 22 are defective. Using Poisson distribution, find that a sample of 300 shirts contain Less than 2 defective shirts A. 0. B. 0. C. 0. D. 0. ANSWER: A. A missile radar detection system consists of two radar screens. The probability that any of the radar screens will detect an incoming missile is 0.95. If a missile enters the detection space of this radar, what is the probability that at least one of the radar screens will detect it? (Assume that detections are independent events) A. 0. B. 0. C. 0. D. 0. ANSWER: A. A local news channel has conducted an opinion poll for constructing more dams in the country. The poll results indicate that 70% of the participants support the idea, 15% are against the idea and 15% are undecided. If a sample of six participating viewers is selected at random, determine the probability that At least five viewers will support the idea A. 0. B. 0. C. 0. D. 0. ANSWER: A.
People of Greenland have a mean height of 160 cm with a standard deviation of 15 cm. If a random sample of size 40 is taken, what is the probability that the sample mean height shall lie between 157 cm and 165 cm? A. 0. B. 0. C. 0. D. 0. ANSWER: A. If two fair dice are rolled together, what is the probability of getting a total of 7 or more? A. 0. B. 0. C. 0. D. 0. ANSWER: A. If two fair dice are rolled together, what is the probability of getting a total of 7 or less? A. 0. B. 0. C. 0. D. 0. ANSWER: A. If two fair dice are rolled together, which of the following is more likely: (a) Getting a total of 7 or more, or (b) Getting a total of 7 or less A. Both are equally likely B. (b) C. (a) D. None of these ANSWER: A. In a group of 12 international referees, there are three from Africa, four from Asia and five from Europe. To officiate at a tournament, three referees are chosen at random from the group. Find the probability that A referee is chosen from each continent A. 0. B. 0. C. 0. D. None of these ANSWER: A. In a group of 12 international referees, there are three from Africa, four from Asia and five from Europe. To officiate at a tournament, three referees are chosen at random from the group. Find the probability that Two referees are chosen from Asia. A. 0. B. 0. C. 0. D. 0. ANSWER: A. In a group of 12 international referees, there are three from Africa, four from Asia and five from Europe. To officiate at a tournament, three referees are chosen at random from the group. Find the probability that All three referees are chosen from the same continent. A. 0. B. 0. C. 0. D. 0. ANSWER: A.
A husband and wife were interviewed for two different posts in the same organization. The probability of husband’s selection is 1/7 and that of wife’s selection is 1/5. What is the probability that Both of them will be selected. A. 0. B. 0. C. 0. D. 0. ANSWER: A. A husband and wife were interviewed for two different posts in the same organization. The probability of husband’s selection is 1/7 and that of wife’s selection is 1/5. What is the probability that None of them will be selected. A. 0. B. 0. C. 0. D. 0. ANSWER: A. A husband and wife were interviewed for two different posts in the same organization. The probability of husband’s selection is 1/7 and that of wife’s selection is 1/5. What is the probability that Only one of them will be selected. A. 0. B. 0. C. 0. D. 0. ANSWER: A. A fair dice is rolled thrice. What is the probability that each time a six will appear? A. 1/ B. 1/ C. 1/ D. None of these ANSWER: A. A binomial random variable has a mean of 200 and standard deviation of 10. Find the values of ‘n’ and ‘p’. A. n = 400, p = 1/ B. n = 300, p = 1/ C. n = 500, p = 1/ D. n = 200, p = 1/ ANSWER: A. A training program has been designed to upgrade the supervisory skills. Supervisors take different number of hours to complete the program. A study of past participants indicate that the mean length of time spent on the program is 500 hours with a standard deviation of 100 hours. What is the probability that a randomly selected candidate will require less than 500 hours to complete the program? A. 0. B. 0. C. 0. D. 0. ANSWER: A. If two dice are rolled, what is the probability that either the sum of the two or will be seven or at least one of the dice will show the number 5? A. 15/ B. 10/ C. 16/
A. 0.
B. 0.
C. 0.
D. 0.
ANSWER: A.
At a university, 40% of the students take Statistics without Mathematics and 25% students take Mathematics without Statistics. 12% of the students take both. If a student is randomly selected from a Statistics class, what is the probability that he or she has also taken Mathematics? A. 0. B. 0. C. 0. D. 0. ANSWER: A. The wholesaler of a toy has 1000 pieces in stick, out of which 200 pieces are slightly defective, mixed randomly with each other. A retailer buys a dozen toys. What is the probability that 10 toys are defect free? A. 0. B. 0. C. 0. D. 0. ANSWER: A. The driving time of an executive from home to office is normally distributed with a mean of 35 minutes and a standard deviation of 8 minutes. Assuming that the total number of working days in a year are 300, you are required to calculate the number of days in which he is expected to drive to work in more than or equal to 40 minutes? A. 80 days B. 75 days C. 85 days D. None of these ANSWER: A. The driving time of an executive from home to office is normally distributed with a mean of 35 minutes and a standard deviation of 8 minutes. Assuming that the total number of working days in a year are 300, you are required to calculate the number of days in which he is expected to drive to work in less than or equal to 30 minutes? A. 80 days B. 75 days C. 85 days D. None of these ANSWER: A. A person is contesting for the directorship of two companies A & B. his success chances for company A is 70% and the possibility for company B is 0.5. What is the probability that he will become director of both the companies? A. 0. B. 0. C. 0. D. 0. ANSWER: A. A person is contesting for the directorship of two companies A & B. his success chances for company A is 70% and the possibility for company B is 0.5. What is the probability that he will become director of at least one of the companies? A. 0.
B. 0.
C. 0.
D. 0.
ANSWER: A.
A person is contesting for the directorship of two companies A & B. his success chances for company A is 70% and the possibility for company B is 0.5. What is the probability that he will not become director of any of the two companies? A. 0. B. 0. C. 0. D. 0. ANSWER: A. Among 18 members of a cricket club, there are two wicket keepers and 5 bowlers. In how many ways can a team of 11 members be chosen so as to include at least one wicket keeper and at least three bowlers? A. 12144 B. 14122 C. 11422 D. 22144 ANSWER: A. Seventy-five percent of youths 12-15 years of age have a blood pressure less than 136. What is the probability that a sample of 12 youths of that age group will include exactly 4 who have a blood pressure of greater than 136? A. 0. B. 0. C. 0. D. None of these ANSWER: A. Seventy-five percent of youths 12-15 years of age have a blood pressure less than 136. What is the probability that a sample of 12 youths of that age group will include at least 4 who have a blood pressure greater than 136?? A. 0. B. 0. C. 0. D. 0. ANSWER: A. The probability that a car will have a flat tyre while driving through a certain tunnel is 0.00006. Use the Poisson approximation to binomial distribution to find the probability that at least 2 out of 10,000 cars passing through the tunnel will have flat tyres. A. 0. B. 0. C. 0. D. 0. ANSWER: A. Find the values of –Z and Z if the standard normal curve area between –Z and Z is 0. A. 2. B. 2. C. 1. D. 1. ANSWER: A. The normal distribution has a mean of 61.60. Find its standard deviation if 20% of the area under curve lies to the right of x = 70.
Suppose a population consists of 15 items, 10 of which are acceptable. A sample of 4 items is selected without replacement. What is the probability that exactly 3 are acceptable? A. 600/ B. 500/ C. 400/ D. 360/ ANSWER: A. If 8 members of a tennis club are classified A players, 6 are classified B players and 10 are classified C players, in how many ways can 2 players from each group be chosen to represent the club? A. 18900 B. 19800 C. 10890 D. 19880 ANSWER: A. The Board of Directors of a company consists of 8 men and 4 women. A 4-member committee is to be chosen at random from the board. What is the probability that all 4 members of the committee will be women? A. 0. B. 0. C. 0. D. None of these ANSWER: A. The Board of Directors of a company consists of 8 men and 4 women. A 4-member committee is to be chosen at random from the board. What is the probability that all 4 members of the committee will be men? A. 0. B. 0. C. 0. D. 0. ANSWER: A. It is estimated that 0.5% of the callers to a department will receive a busy signal. Using the Poisson distribution, find the probability that of 1200 callers at least 5 will receive busy signal? A. 0. B. 0. C. 0. D. 0. ANSWER: A. The weights of a group of children are approximately normally distributed with mean = 15. kg and standard deviation = 1.75 kg. What proportion of children will weigh between 13 and 16 kg? A. 0. B. 0. C. 0. D. 0. ANSWER: A. The weights of a group of children are approximately normally distributed with mean = 15. kg and standard deviation = 1.75 kg. What proportion of children will weigh 13 Kg or more? A. 0. B. 0. C. 0.
D. 0.
ANSWER: A.
The weights of a group of children are approximately normally distributed with mean = 15. kg and standard deviation = 1.75 kg. The heaviest 5% of the children are to be studied further. What is the cutoff point between those who will be studied and those who will not be studied? A. 17.87 kg B. 18.77 kg C. 15.24 kg D. None of these ANSWER: A. Out of 17 males and 23 female students, two students are selected at random without replacement from the class. Find the probability that the first student selected is female and second is male. A. 0. B. 0. C. 0. D. 0. ANSWER: A. As per current medical research 30 percent of population suffers from common cold each winter. A group of 12 persons is selected randomly. Calculate the probability that exactly 5 in the group will have the common cold this winter. A. 0. B. 0. C. 0. D. 0. ANSWER: A. As per current medical research 30 percent of population suffers from common cold each winter. A group of 12 persons is selected randomly. Calculate the probability that at least 5 in the group will have common cold this winter. A. 0. B. 0. C. 0. D. None of these ANSWER: A. As per current medical research 30 percent of population suffers from common cold each winter. A group of 12 persons is selected randomly. Calculate the mean and variance of the number in the group that will have common cold this winter. A. Mean = 3.6, Variance = 2. B. Mean = 4.6, Varaince = 1. C. Mean = 1.6, Variance = 3. D. None of these ANSWER: A. The probability that a computer recovers from a rare virus attack is 0.4. If 15 computers are known to have contracted with this virus, find the probability that at least 12 computers survive. A. 0. B. 0. C. 0. D. None of these ANSWER: A.
B. 0.
C. 0.
D. 0.
ANSWER: A.
In graduate school of business an acceptance rate of 30% was reported. If 10 applicants are selected at random, find the probability that fewer than 8 were accepted. A. 0. B. 0. C. 0. D. None of these ANSWER: A. In graduate school of business an acceptance rate of 30% was reported. If 10 applicants are selected at random, find the probability that between 5 and 8 (including 5 and 8) were accepted.. A. 0. B. 0. C. 0. D. None of these ANSWER: A. An analysis of the test scores for an examination revealed that they approximate a normal distribution with a mean of 75 and a standard deviation of 8. The examiner wants to award “A” grade to upper 10 percent of test grades. What is the dividing point between an A and a lower grade? A. 85. B. 82. C. 52. D. 58. ANSWER: A. Grades on a national aptitude test have been found to be normally distributed with a mean of 250 and a standard deviation of 25. What is the probability that a student selected at random will score between 230 and 256? A. 0. B. 0. C. 0. D. 0. ANSWER: A. On a single toss of a pair of fair dice, what is the probability that a sum of 7 appears and both dice show a number less than 4? A. 0 B. 0. C. 0. D. None of these ANSWER: A. A firm has two vacancies for trainee students. In the past 40% of the students who were offered the training contract did not join. If 2 students are offered training contract, what is the probability that at least one will join? A. 0. B. 0. C. 0. D. 0. ANSWER: A.
A random sample of size 15 is taken from a normally distributed population with a mean 60 and standard deviation 4. Find the probability that the mean of the sample is less than 58. A. 0. B. 0. C. 0. D. 0. ANSWER: A. A firm which conducts consumer surveys by mail has found that 30% of the families receiving a questionnaire will return it. In a survey of 10 families, what is the probability that exactly five families will return the questionnaire? A. 0. B. 0. C. 0. D. 0. ANSWER: A. Records show that the probability is 0.0006 that a car will have a flat tyre while driving through a tunnel. Use the Poisson approximation to the Binomial distribution to find the probability that at least 2 out of 10,000 cars passing through the tunnel will have flat tyres. A. 0. B. 0. C. 0. D. 0. ANSWER: A. The names of 4 men and 6 women are written on a slips of paper and placed in a box. Four names are drawn without replacement. What is the probability that 2 are men and 2 are women? A. 0. B. 0. C. 0. D. 0. ANSWER: A.
