An unknown distribution has a mean of 80 and a standard deviation of 12. A sample size of 95 is drawn randomly from the population.

Find the probability that the sum of the 95 values is less than 7,400.

(give the answer to 4 decimal places)

(a)  

An unknown distribution has a mean of 80 and a standard deviation of 12. A sample size of 95 is drawn randomly from the population.

Find the sum that is two standard deviations above the mean of the sums.

(give the answer to 2 decimal places)

(a)  

An unknown distribution has a mean of 80 and a standard deviation of 12. A sample size of 95 is drawn randomly from the population.

Find the sum that is 1.5 standard deviations below the mean of the sums.

(give the answer to 2 decimal places)

(a)  

The distribution of results from a cholesterol test has a mean of 180 and a standard deviation of 20. A sample size of 40 is drawn randomly.

Find the probability that the sum of the 40 values is greater than 7,500.

(give the answer to 4 decimal places)

(a)  

The distribution of results from a cholesterol test has a mean of 180 and a standard deviation of 20. A sample size of 40 is drawn randomly.

Find the probability that the sum of the 40 values is less than 7,000.

(give the answer to 4 decimal places)

(a)  

The distribution of results from a cholesterol test has a mean of 180 and a standard deviation of 20. A sample size of 40 is drawn randomly.

Find the sum that is one standard deviation above the mean of the sums.

(give the answer to 2 decimal places)

(a)  

The distribution of results from a cholesterol test has a mean of 180 and a standard deviation of 20. A sample size of 40 is drawn randomly.

Find the sum that is 1.5 standard deviations below the mean of the sums.

(give the answer to 2 decimal places)

(a)  

The distribution of results from a cholesterol test has a mean of 180 and a standard deviation of 20. A sample size of 40 is drawn randomly.

Find the percentage of sums between 1.5 standard deviations below the mean of the sums and one standard deviation above the mean of the sums.

(give the answer to 2 decimal places)

(a)  

A researcher measures the amount of sugar in several cans of the same soda. The mean is 39.01 with a standard deviation of 0.5. The researcher randomly selects a sample of 100.

. Find the probability that the sum of the 100 values is greater than 3,910.

(give the answer to 4 decimal places)

(a)  

A researcher measures the amount of sugar in several cans of the same soda. The mean is 39.01 with a standard deviation of 0.5. The researcher randomly selects a sample of 100.

. Find the probability that the sum of the 100 values is less than 3,900.

(give the answer to 4 decimal places)

(a)  

A researcher measures the amount of sugar in several cans of the same soda. The mean is 39.01 with a standard deviation of 0.5. The researcher randomly selects a sample of 100.

.Find the sum with a z–score of –2.5.

(give the answer to 2 decimal places)

(a)  

A researcher measures the amount of sugar in several cans of the same soda. The mean is 39.01 with a standard deviation of 0.5. The researcher randomly selects a sample of 100.

.Find the sum with a z–score of 0.5.

(give the answer to 2 decimal places)

(a)  

An unknown distribution has a mean of 12 and a standard deviation of one. A sample size of 25 is taken. Let X = the object of interest.

What is the mean of ΣX?

(a)  

An unknown distribution has a mean of 12 and a standard deviation of one. A sample size of 25 is taken. Let X = the object of interest.

What is the standard deviation of ΣX?

(a)  

An unknown distribution has a mean of 12 and a standard deviation of one. A sample size of 25 is taken. Let X = the object of interest.

What is P(Σx = 290)?

(a)  

An unknown distribution has a mean of 12 and a standard deviation of one. A sample size of 25 is taken. Let X = the object of interest.

What is P(Σx > 290)?

(a)  

An unknown distribution has a mean of 25 and a standard deviation of six. Let X = one object from this distribution. What is the sample size if the standard deviation of ΣX is 42?

(a)  

A market researcher analyzes how many electronics devices customers buy in a single purchase. The distribution has a mean of three with a standard deviation of 0.7. She samples 400 customers.

. What is the z-score for Σx = 840?

Give your answer to 2 decimal places.

(a)  

A market researcher analyzes how many electronics devices customers buy in a single purchase. The distribution has a mean of three with a standard deviation of 0.7. She samples 400 customers.

What is P(Σx < 1,186)?

Give your answer to 4 decimal places.

(a)