Statistics and Probability Answers

Suppose the mean number of days to germination of a variety of seeds is 34, with a standard deviation of 4.3 days. What is the probability that the mean germination time of a sample of 250 seeds will be within 0.5 days of the population mean?

In the Framingham Offspring study 1573 subjects were on anti-hypertensive medication out of 3645 total subjects. What is the length of the 99 percent confidence interval for this data.

Note: Round your answer to 4 decimal places.

A sample of Alzheimer's patients are tested to assess the amount of time in stage IV sleep. It has been hypothesized that individuals suffering from Alzheimer's Disease may spend less time per night in the deeper stages of sleep. Number of minutes spent in Stage IV sleep is recorded for sixty-one patients. The sample produced a mean of 59 minutes with a standard deviation of 27 minutes of stage IV sleep over a 24 hour period of time. What is the length of the 95 percent confidence interval for this data.

Note: Round your answer to 4 decimal places.

A process has been developed that can transform ordinary iron into a kind of super iron called metallic glass. Metallic glass is three to four times stronger than the toughest steel alloys. To estimate the mean temperature at which a particular type of metallic glass becomes brittle, 20 pieces of this material were randomly sampled from a recent production run. Each piece was subjected to higher and higher temperatures until it became brittle. The temperature at which brittleness first appeared was recorded for each piece in the sample. The result suggests that the average temperature which brittleness first appeared is about 545 degrees Fahrenheit with a standard deviation of 27 degrees Fahrenheit. Calculate the length of the 95% confidence interval for the mean temperature at which a particular type of metallic glass becomes brittle.

Note: Round your answer to 4 decimal places.

A process has been developed that can transform ordinary iron into a kind of super iron called metallic glass. Metallic glass is three to four times stronger than the toughest steel alloys. To estimate the mean temperature at which a particular type of metallic glass becomes brittle, 20 pieces of this material were randomly sampled from a recent production run. Each piece was subjected to higher and higher temperatures until it became brittle. The temperature at which brittleness first appeared was recorded for each piece in the sample. The result suggests that the average temperature which brittleness first appeared is about 545 degrees Fahrenheit with a standard deviation of 27 degrees Fahrenheit. Calculate the length of the 95% confidence interval for the mean temperature at which a particular type of metallic glass becomes brittle.

Find dy/dx for the equation y= 3x-5/×^2-4x

Solve the sample mean and the probability of each sample mean by constructing all random samples consisting of two observations from the given data. 

Watermelon    

A

B

C

D

E

F

Weight (in pounds)

19

14

15

9

10

17

The number of inquiries received per day by the Office of Admissions in a certain university is shown below. Find the variance

and standard deviation.

Number of inquiries: 20, 21,22,23,24,25, 26

Probability: 0.07, 0.17, 0.26, 0.31, 0.2, 0.13,0.12

The number of inquiries received per day by the Office of

Admissions in a certain university is shown below. Find the variance

and standard deviation.

Number of inquiries: 20, 21,22,23,24,25, 26

Probability: 0.07, 0.17, 0.26, 0.31, 0.2, 0.13,0.12

A population consists of the five measurements 2, 6, 8, 3 & 1. How many different

samples of size n = 2 can be drawn from the population? What is the mean & variance

of the sampling distribution of the sample means? Follow steps 1 to 6.