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DDD The number of games won by a famous basketball team each year from the year 1991 to the year 2000 are 25, 30, 25, 50, 40, 75, 40, 50, 35, and 40. What is the equivalent box-and-whisker plot of the data, among the four plots? DDD View Solution
DDD A company makes wooden wardrobes having a standard height of 55 in., with a standard deviation of 2.5 in. In a random sample of 23 wardrobes, 6 wardrobes measured 58.5 in., 8 wardrobes measured 53.8 in. and 9 wardrobes measured 56 in.. Test at 0.05 level of confidence and find out if the null hypothesis can be accepted.
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DDD A standard notebook is supposed to have on an average, 200 pages, with a standard deviation of 2 pages. From a supply of 2500 notebooks, a random sample of 40 notebooks was taken and found that the mean number of pages in the notebook was 197. Test at the 0.05 level of confidence and find out if the null hypothesis can be accepted. DDD View Solution
DDD A soft drink company claims that the mean quantity of soft drink in a tin is 300 ml with a standard deviation of 5 ml. A random sample of 65 bottles from a shipment had a mean of 296.5 ml. Is the shipment is significantly different from the standard at the 0.05 level of significance? DDD View Solution
DDD Radio tubes manufactured by a company are expected to have a mean lifetime of 400 hours, with a standard deviation of 30 hours. Random samples of 10 tubes were tested. It was found that 3 tubes had a lifetime of 398 hours, 5 of them had a lifetime of 410 hours and 2 had a lifetime of 400 hours. Is this case significantly different from the standard at the 0.05 level of significance? DDD View Solution
DDD A tooth paste tube is supposed to contain 150g of toothpaste, with a standard deviation of 2g. A random sample of 53 tubes is found to have a mean weight of 148.5g. Does this sample differ significantly from the standard at 0.05 level of significance?
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DDD A retail garment shop receives a shipment of trousers, with a standard length of 49.0 in. and a standard deviation of 1.0 inch. A random sample of 32 trousers had a mean length of 48.8 in. Find the 95% confidence interval.
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DDD The mean number of candies in a packet is 175, with a standard deviation of 5 candies. A random sample of 70 packets from a certain shipment has a mean of 174.2 candies. Which of the following statements is true?
1.The null hypothesis is accepted.
2.Standard error = 1.78
3.The shipment is significantly different from the standard at 0.05 level.
4.The 95% confidence interval lies between 173.8 and 176.2 DDD
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DDD The mean score on a standardized test is 100 with a standard deviation of 8. A random sample of 48 scores was found to have a mean of 98. Test at the 0.05 level of confidence and state whether or not to accept the null hypothesis.
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DDD In a class, 70% of the students study economics. If 6 students are selected at random, then what is the probability that all the 6 students study economics. DDD View Solution
DDD In a town T, 30% of the people suffer from some kind of health disorder. If 12 people are selected at random, then find the probability that none of them suffer from any kind of disorder.
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DDD Specify the nature of probability that the following statement denotes:
The probability that it will rain tomorrow is 83%( Weather Department Forecast). DDD
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DDD What type of probability does the statement denote?
The probability that a student will get 60% and above is 0.23. DDD
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DDD Specify the nature of probability that the following statement denotes:
The probability that a new motel venture in the State will succeed is 25%. DDD
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DDD In a school, 40% of the students play basketball. If 400 students are selected at random, then find the mean and variance of the number of students who play basketball.
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DDD An unfair coin has a 60% chance of landing heads-up. If X = 1 represents a coin landing heads-up, and X = 0 represents a coin landing tails-up, then find the sampling distribution of the mean(x¯) for samples of size 3. DDD View Solution
DDD Sarina dropped a marble at random on the arrangement of tiles shown. Find the probability of the stone landing on a pink tile. DDD View Solution
DDD A survey is conducted on the importance of health care for the elderly. The samples below list the percentages of people surveyed in different age groups. Identify the sample which is biased. DDD View Solution
DDD In a survey, 60% of the population said they watch foot ball. Find the odds in favor of watching foot ball. DDD View Solution
DDD The double line graph compares the income of Mr. Jack in 5 months in the years 1991 and 1992. How much more did he earn in August, 1992 than in August, 1991?
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DDD A gas lighter manufacturer claims that the lifespan of his gas lighter has a mean of 48 months and a standard deviation of 6 months. A sample of 50 gas lighters are tested by a consumer advocacy group. Assuming the manufacturer's claims are true, what is the probability that it finds a mean lifetime of less than 46 months? DDD View Solution
DDD A central office operator has observed that the long distance telephone calls are normally distributed with a mean of 6 minutes and a standard deviation of 2 minutes. If random samples of 32 calls were selected, what is the probability that the length of the sample mean time exceeds 7 minutes?
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DDD Jim and Jeff are playing a spinner game.Jim wins if the spinner lands on a odd number and Jeff wins if it lands on an even number. Identify the spinner they made so that each of them have a equally likely chance to win. DDD View Solution
DDD Kim and Joe want to play chess. They want to decide who will make the first move by spinning a spinner. Identify the spinner that does not show equal chances to make the first move.
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DDD Ann′s mother bought a pizza and a hamburger. Ann and Jack both like pizza. They made a spinner to decide who will have the pizza. Find the spinner they made if both of them have equal chances of having the pizza.
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