random samples

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..

The manager of the local branch of a savings bank has determined that 30% of all depositors have multiple accounts at the bank. If a random sample of 200 depositors was selected, what is the probability that sample proportion of depositors will be between 0.30 and 0.33..

A random sample of 200 children were surveyed. 80 children said that they liked reading books by Enid Blyton. Out of 600 children, how many could be predicted to like books by Enid Blyton? => 240 or 160 or 480 or 400..

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 null h..

The 95% confidence interval for the mean number of mangoes in a carton is between 48.12 and 51.88. If a random sample of 27 cartons were used to determine this interval, what was the standard deviation? => 2 or 3 or 4 or 5..

The 95% confidence interval for the mean number of sheets of paper in a ream is between 452.76 and 447.24. If the standard deviation is 10 papers, find the size of the random sample that was used to determine this interval. => 5.52 or 50 or 1.41 or 7.09..

Seventy-seven percent of students who have a computer at home have a webcam attached to it. In a random sample of 290 homes, what is the probability that more than 200 and less than 230 students have a web-cam attached to their computers? => 19.28% or 80.58% or 49.93% or 30.65% ..

The probability that a person selected prefers to go out on a shopping is 0.7. A random sample of 100 people was selected. Find the probability that the proportion of people who prefer to go out on a shopping is greater than 75%. => 16.4% or 11.71% or 88.29% or 83.6%..

A random sample of the daily amount of fuel (in litres) used for running power and heating systems in a manufacturing unit is listed here. Estimate the mean fuel consumption with 90% confidence. => 974.6 < μ < 1233.7 or 1084.8 < μ < 1123.6 or 900 < μ <..

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..