According to the American Red Cross, 8% of all Connecticut residents have Type B blood. A random sample of 25 Connecticut residents is taken. X=the number of CT residents that have Type B blood, of the 25 sampled. What is the standard deviation of the random variable X?

60% of all the students passed an exam. If a random sample of 10 students is selected, What is the mean and the standard deviation ?

You have a sample of 48 randomly selected Vancouverites. On average (the sample mean), the people in your sample spent 425 hours eating food in 2020. The least time a person in the sample spent eating food in 2020 is 367 hours and the most time a person in the sample spent eating food in 2020 is 484 hours. What would be your best guess about the population standard deviation of the time a Vancouverite spent eating food in 2020? Give the number and explain (including assumptions you make about the population distribution).

Use software or a calculator to find the​ range, variance, and standard deviation of the following body​temperatures, in degrees​ Fahrenheit, taken at​ 12:00 A.M. I don't remember how to find variance on a TI-83 Plus calculator and translate standard deviation. HELP!

A particular fruit's weights are normally distributed, with a mean of 454 grams and a standard deviation of 36 grams.The heaviest 18% of fruits weigh more than how many grams?Give your answer to the nearest gram.

Cody took his first physics exam and scored an 80. The population mean for this exam is 70, and the standard deviation is 5. What is the probability of selecting a person with a score greater than Cody’s?

All California 5th graders take a standardized test. The mean for the population of 5th graders is 68.9 and the standard deviation for the population is 10. What is the probability of randomly selecting a student who scored   a. ≥ 85? b. less than or equal to 85? c. between 80 & 85? d. between 60 & 85?

It is known that 41% of the population in the United States have brown eyes. Find the mean and standard deviation for the number of brown eyed people in a random group of 25 people in the United States. I cannot for the life of me figure this problem out.

The NJ Department of Health has reported the average life span of NJ residents is 81 years. If the standard deviation is σ = 4 years, what is the probability of a person living to at least 92 years of age?

A single fair die is rolled seven times. Find the mean and standard deviation of the number of times a 3 appears.