sample mean

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. State the null hypothesis and alternative hypothesis. => H o : The mean score = 100, H a : The mean score ≠ ..

In a NBA playoff season the average number of points scored in a game was 200. Assume the standard deviation was 75. If a random sample of 20 games is selected, then what is the probability that the mean of the sample is lesser than 220? => 17.20% or 33.80% or 67.20% o..

A report states that the average height of three-year old children in rural areas was 89.5 cm with a standard deviation of 5 cm. In order to check these figures, the heights of a sample of 100 three-year old children from the rural area were measured. Assuming the report as true, what is ..

The average annual temperature of a place is 68°F and the standard deviation is 10°F. If a random sample of 36 days is taken, then find the probability that the mean sample temperature is less than 70°F? => 89.62% or 39.62% or 10.38% or 60.38%..

95% confidence interval of a population mean worked out on a sample size of 10 is, 0.26 < μ < 0.38. What is the likely 95% confidence interval of the mean of the same population worked out on a sample size of 20? => 0.28 < μ < 0.36 or 0.24 &..

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. => The null hypothesis is accepted or ..

The average protein content in different types of nuts is 20 g, and the standard deviation is 5 g. Assume the variable is normally distributed. If a sample of 16 nuts are selected, then find the probability that the mean of the sample will be greater than 22 g. => 65.5..

A sample of scores of 250 candidates has a mean of 47.2 with a standard deviation of 18.6. Find 90% and 95% confidence interval of the population mean and determine which is larger? => (45.3, 49.1) and (44.9, 49.5) and 95% or (45.26, 49.14) and (44.89, 49.51) and 90% o..

A sample of the reading scores of 35 sixth graders has a mean of 82. If the 95% confidence interval for the population mean of the reading scores of all fifth graders is between 77 and 87, then which among the following choices represents the 99% confidence interval? =..

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? => Yes or No..