You are a researcher studying the lifespan of a certain species of bacteria.  A preliminary sample of 40 bacteria reveals a sample mean of ¯x=68x¯=68 hours with a standard deviation of s=6.2s=6.2  hours.  You would like to estimate the mean lifespan for this species of bacteria to within a margin of error of 0.65 hours at a 98% level of confidence. What sample size should you gather to achieve a 0.65 hour margin of error? Round your answer up to the nearest whole number. n =    bacteria

Q: A random sample of 14 nurses in a large hospital showed that they worked on average 44.8 hours per…

A: The random variable time follows normal distribution. The sample size is 14. The sample mean is…

Q: The average U.S. adult weight is 180 lbs. with a standard deviation of 15 lbs. A nutritional…

A: Given: X=Weight of US adult. Sample mean, x=165 Sample size, n=100 Population mean, μ=180 Standard…

Q: A sample of 30 washing machines yields a mean replacement time of 10 years. Assuming that the…

A:

Q: o=58. From sample sizes of 36 adults find the proportion of sample means having values of at least…

A: here , sample size  = 36 population  mean = 162 population standard deviation = 58

Q: You are a researcher studying the lifespan of a certain species of bacteria.  A preliminary sample…

A: The provided information are: Population standard deviation σ=4 Margin of error (E) = 0.5 Confidence…

Q: A shareholders' group is lodging a protest against your company. The shareholders group claimed that…

A: We want to find the test statistic and p value

Q: It takes an average of 10 minutes for blood to begin clotting after an injury.  An EMT wants to see…

A: Given, population mean,µ = 10 population standard deviation (σ) = 3.5 sample size (n)  = 54 sample…

Q: The average income of 15 families who reside in a large metropolitan East Coast city is $62,456. The…

A: Given that    Sample sizes n1=14   , n2=11        Sample means X̄1=62456     , X̄2= 60213    s1…

Q: a) What is the setup for your null and alternative hypothesis? b) What is the value of the test…

A: Here AS PER POLICY I HAVE CALCULATED 3 SUBPARTS PLZ REPOST FOR REMAINING PARTS WITH NOTE I NEED…

Q: A physics lab instructor wants to estimate the time required for physic students to complete a…

A: Given that  Standard deviation = 16 Margin of error = 5

Q: We have a recent set of data of n=15 dodge chargers, the sample mean = 30 miles per gallon, the…

A: Consider that μ is the population mean mileage.

Q: The mean pulse rate for adult males is approximately 61.4 beats per minute. In a sample of 27…

A:

Q: An electrical firm manufactures light bulbs that have a length of life that is approximately…

A: Solution: From the given information, confidence level is 0.94, σ=25 and E=12.

Q: Age at onset of dementia was determined in the general population to be 70 and standard deviation…

A: Given Information: Age at onset of dementia was determined in the general population to be mean 70…

Q: You may believe that each day, men and women spend about the same amount of time using Facebook. We…

A: Hypothesis to be tested: H0: μ men = μ women  H1: μ men ≠ μ women Let, men and women are the…

Q: It takes an average of 12.6 minutes for blood to begin clotting after an injury.  An EMT wants to…

A: Hey there! Thank you for posting the question. Since your question has more than 3 parts, we are…

Q: The Mental Development Index (MDI) is a measure used in observing infants over time. Suppose MDI…

A: Suppose the random variable x defines the MDI.

Q: To estimate the mean height μ of male students on your campus, you will measure an SRS of students.…

A: From the provided information, The height of young men are approximately normal with standard…

Q: A shareholders' group is lodging a protest against your company. The shareholders group claimed that…

A:

Q: The average length of service for the employees at a company is 9.3 years with a standard deviation…

A: Average=mu=9.3 , Standard deviation=sigma=4.2 , Z-score=Z=1.6 Let X=Length of service…

Q: You are a researcher studying the lifespan of a certain species of bacteria. A preliminary sample of…

A:

Q: tallation of a new computer plug in station? After the plug in station was built, the librarian…

A: The mean = 57.8The standard deviation = S = 6The sample size [n] =51Use t-distribution.

Q: Identify a null and alternative hypothesis for a two-sided test.     Calculate a z score for this…

A: Given that, Population mean (μ) = 27 Standard deviation (σ) = 15 Sample size (n) = 100 Sample mean…

Q: A researcher studying the lifespan of a certain species of bacteria. A preliminary sample of 25…

A: It is given that the confidence level is 0.99, the standard deviation is 4.4, and the margin of…

Q: A random sample of hybrid vehicle fuel consumptions has a sample mean of x¯=53.2 mpg and sample…

A: We have given that the sample mean 53.2 and standard deviation 4.8.

Q: A standardized test is given to a sixth grade class. Historically the mean score has been 143 with a…

A: Suppose σ is the population standard deviation of the performance scores.

Q: A sample of size 60 will be drawn from a population with mean 31 and standard deviation 6 .Find…

A: Given that.   X~N( μ , ?)   μ=31     , ?=6   Z-score =( x - μ )/?

Q: A researcher studying the lifespan of a certain species of bacteria. A preliminary sample of 35…

A:

Q: A shareholders' group is lodging a protest against your company. The shareholders group claimed that…

A:

Q: A standardized test, deigned to measure the mathematical skill level of seventh graders is said to…

A: Given information: μ=75, n=25x¯=79, s=10 Null hypothesis: H0 : μ=75 Alternative hypothesis: HA :…

Q: (a) Identify Ho and H₂. Choose the correct answer below. Ο Α. Ηο: μ = 40 H₂:μ#40 OC. Ho: μ240.6 Ha:…

A: Given that  Sample size n =30 Sample mean =40.6 Population standard deviation =7.7

Q: A shareholders' group is lodging a protest against your company. The shareholders group claimed that…

A: Denote μ as the true mean tenure for a chief executive office.

Q: A researcher at Central Hartford University is testing out a new super long-lasting chewing gum.  He…

A:

Q: A shareholders' group is lodging a protest against your company. The shareholders group claimed that…

A: Solution: Given information : n= 67 Sample size  μ=11 years Population meanx= 9 years Sample means=…

Q: You are a researcher studying the lifespan of a certain species of bacteria.  A preliminary sample…

A: Given,Sample standard deviation, s = 5.4 hours Margin of error, E = 0.5 hourConfidence level, C =…

Q: How large of a sample is required if we want to estimate the mean price of a five year old Corvette…

A: Obtain the critical value at 90% confidence level:It is given that the standard deviation value is…

Q: If the standard deviation of a sample is 9. How many subjects would we need to have 80% power to…

A: Given: Sample standard deviation s = 9 Difference d = 9 Significance level α = 0.025 Formula Used: n…

Q: We have a recent set of data of n=30 Americans, the sample mean = 14 hours per day, the standard…

A: The sample mean and population mean is whether related or not is calculated using the z test when…

Q: A shareholders' group is lodging a protest against your company. The shareholders group claimed that…

A: Given, Sample size = 120 Sample mean = 7.3 Sample standard deviation = 5.8   Set up the null and the…