Statistics and Probability Answers

There are five card in a box containing the numbers 1,3,5,7 and 9. A sample of size 3 is to be drawn at a time. Construct the sampling distribution of the mean.

a.) How many possible samples can be drawn?

b.) List all the possible samples and the corresponding means.

c.) Construct the sampling distribution of the sample means.

d.) Draw the histogram for the sampling distribution of the sample means.

e.) What is the shape of the histogram of the sampling distribution of the sample means?

The heights of grade 11 male students are normally distributed with a mean of 65 inches and a standard deviation 2.25 inches. (a) Find the values of 45.75 inches and 72.5 inches. (b) What is the probability that a randomly chosen member of the group has height x berween 60 inches and 70 inches?

The weight of goats at a farm is normally distributed with a mean of 60 kg. A truck used to transport goats can only acommodate not more than 650 kg.If goats are selected at random from the population, what is the probability that the total weight exceeds the maximum weight?

The larger the standard deviation of a distribution, the more heterogeneous the scores in that distribution. Is this statement true?explain.

A population consists of the numbers 2, 4, 5, 9, 10. List all possible sample size of 3 from this population without replacement and determine the mean of each sample.

1. The probability that a student must stop at any one traffic light going to NUST from Havana is 0.2. There are 15 traffic lights on the Journey.

a) what is the probability that a student will stop at exactly two of the 15 set of traffic lights?

b) what is the probability that a student will stop at 3 or more of the 15 set of traffic lights?

A teacher realizes that his students' marks on a statistic test are normally distributed with a mean of 62 and a standard deviation of 15. If the teacher wishes to assign minimum marks for grade B is referring to the top 30 per cent of the students' marks in the class, how many marks are required to get a minimum mark for grade B?

Determine the area under the standard normal distribution curve to left of -0.73.

Determine the area under the standard normal distribution curve between -0.91 and 2.5.

Determine the area under the standard normal distribution curve between -0.91 and 2.5.