sample test

Suppose 20% of all voters favour candidate A. Pollsters take a sample of 600 voters. Determine the probability that the sample proportion will be between 0.18 and 0.22. => 19.36% or 40.32% or 80.64% or 89.4%..

Select the correct statement(s). I. Every unit in the sample has an equal probability of being included in the population. II. If repeated samples are taken from a population and the same statistic is calculated from each sample then the statistics will not vary. III. ..

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 ..

From a random sample of 36 restaurents in a particular city, the average cost per dinner was reported as $26.50. What is the test value if the population mean is $25 with standard deviation of $4.40 and α = 0.01? Can we say that the sample comes from this populat..

A survey reports that more than 20% of the families in the population own one child under 18 years of age. To test this report, a researcher selected a sample of 200 families and found that 46 of them own one child under the age of 18 years. At α = 0.05, is there enough ev..

The average income of 50 taxi drivers was found as $26,358. Find the test value for a population mean of $25,767 and standard deviation of $1105. Does the sample come from this population? α = 0.01. => 3.782, no or 26.742, no or 1.635, yes or 1.891, yes..

The average time a person spoke over the cell phone while driving in a day was reported as more than 14.5 minutes. A researcher wished to test this report. He selected a sample of 100 persons for his study and found that the mean was 15.6 minutes. At α = 0.01, what will be..

A manufacturer claims that the average life time of an electronic component is at least 40 hours. A sample of 50 components average life time was calculated, and the decision was to reject the null hypothesis from the test statistic. Which of the following statements states the ..

The report of a municipal corporation states that the average monthly electricity bill of a household in the city is $75. To test this report, a researcher selected a sample of 120 residential electricity bills and found the mean as $76.50 with a standard deviation of $15. At &a..

Select the correct statement(s). I. A population is a group of subjects selected from a sample. II. A sample is a group of subjects selected from a population. III. A population consists of all subjects that are under study. IV. Statistical studies always use samples. ..