. A company purchases bulbs that are supposed to burn for a mean life of at least 2425 hours, with a standard deviation of 225 hours. A sample of 81 bulbs is taken, with the mean of 2500 hours, α = 0.01. Find z value:

Q: Suppose that replacement times for washing machines are normally distributed with a mean of μ= 8.7…

A: Let ,  random variable X be the replacement times for washing machines  The random variable X…

Q: According to a survey, the mean height for men is 69.1 inches. In a sample of 280 men between the…

A: given data claim : μ < 69.1n = 280x¯ = 68.9σ = 2.88

Q: car owner determines that annual repair costs (R) can be estimated based on the number of miles…

A: The property of the standard deviation is,.

Q: In a sample of 13 randomly selected high school seniors, the mean score on a standardized test was…

A: Given information, x¯=1185s=160.7μ=1016n=13 t value: t=x¯-μsn =1185-1016160.713  =3.79

Q: In a sample of 250 student GPAs, the mean is 3.25 with a standard deviation of 0.22. Use the…

A: From the given information, there are 250 student GPAs with the sample mean 3.25 and the standard…

Q: On a recent calculus exam, a class mean was 73 with a standard deviation of 2.7. Calculate the…

A:

Q: A survey collected data from a random sample of 121 people living in Jade city. The sample average…

A: It is given that the sample mean is 23.28.Using the given information, the standard error of the…

Q: An experiment was conducted to determine whether there is a significant difference among the mean…

A: Given, A B C D E 15 21 22 10 6 18 13 19 14 11 9 20 24 21 15 16 17 21 13 8

Q: A drug to reduce fever was given to a random saple of 8 patients who suffered from high fever. The…

A: Solution: Before After d = Before - After  (d-d) (d-d)2 39.2 40 -0.8 -1.5 2.25 38.5 37.9 0.6…

Q: Assume that a certain bacteria contaminated in a gallon of milk is normally distributed with a mean…

A: Given,mean(μ)=2500standard deviation(σ)=46.3

Q: A population has mean  =μ19  and standard deviation  =σ5 . Find  μx  and  σx  for samples of…

A:

Q: A researcher is conducting a study where participants exercise on a treadmill for 40 minutes and…

A: From the provided information,Z-score = 2

Q: A simple random sample of six values had mean x = 13.00 and standard deviation s = 7.155. Calculate…

A: Given,

Q: A nutritionist claims that the mean tuna consumption by a person is 3.1 pounds per year. A sample…

A: Solution: Let X be the tuna consumption by a person. From the given information, n=90, x-bar=2.9 and…

Q: The average production of peanuts in Virginia is 3,000 pounds per acre. A new plant food has been…

A: Let be the population mean production of peanuts in Virginia. The average production of peanuts in…

Q: The blood platelet counts of a group of women have a bell-shaped distribution with a mean of 264.3…

A: given data bell shaped (normal) distribution μ = 264.3σ = 61.1

Q: A random sample of 88 eighth grade​ students' scores on a national mathematics assessment test has…

A: Given Information: Sample size (n) = 88 Sample mean (x¯) = 283 Population standard deviation (σ) =…

Q: The lifetime of a certain type of automobile tire (in thousands of miles) is normally distributed…

A: Given ,          Mean μ=40          Standard deviation σ=5

Q: A random sample of adult female reaction times has a sample mean of x¯=394.3 milliseconds and sample…

A: We first find 140.5 is how many SD (standard deviation) away from the mean 394.3 So, 140.5 is 3SD…

Q: A specific product has demand during lead time of 100 units, with a standard deviation during lead…

A:

Q: Toyota needs to determine the average service time to check and repair 80% of their customer’s…

A: Here, σ=300 secs60=5 minutes, z=0.84, x=30 minutes.

Q: In a sample of 15 randomly selected high school seniors, the mean score on a standardized test was…

A: Step 1: Identify the formula for t-value (a t-distribution will be used since only the sample…

Q: The brain volumes ​(cm3​) of 50 brains vary from a low of 902 cm3 to a high of 1478 cm3. Use the…

A: Given Information:    Maximum=1478Minimum=902

Q: A nutritionist claims that the mean tuna consumption by a person is 3.6 pounds per year. A sample of…

A: Given, A nutritionist claims that the mean tuna consumption by a person is 3.6 pounds per year. A…

Q: deviation s = 0.1. Is there sufficient evidence in the sample to suggest that the mean nicotine…

A: here given, sample mean  = 1.53 sample standard deviation  = s= 0.1 significance level = 0.01

Q: The combined SAT scores for the students at a local high school are normally distributed with a mean…

A: Let "X" be the combined SAT scores for the students at a local high school

Q: A random sample of 51 adult coyotes in a region of northern Minnesota showed the average age to be x…

A:

Q: A random sample of 46 adult coyotes in a region of northern Minnesota showed the average age to be…

A: a) The level of significance is α = 0.01.

Q: A drug to reduce fever was given to a random saple of 8 patients who suffered from high fever. The…

A:

Q: onsider a population that has a score of X = 15 associated with a z-score of +1.50. What does this…

A: Given: X=15  z-score =+1.50

Q: Suppose that replacement times for washing machines are normally distributed with a mean of μ=8.7…

A: For a variable distributed normally, i.e for X~N(μ, σ) the z-score for X is, Z=X-μσ; Z~N(0,1)…

Q: Suppose babies born after a gestation period of 32 to 35 weeks have a mean weight of 2500 grams and…

A: Given that the mean of the gestation period of 32 to 35 weeks is 2500 and standard deviation is 800.…

Q: The antibody production of 12 male red-winged blackbirds before and after receiving testosterone…

A:

Q: Hawaiians are known to have an active lifestyle, enjoying the fresh air and natural beauty the…

A: State the appropriate hypothesis:Denote the population mean life expectancy of the US population…