You are going to estimate how long a person holds down a button on their calculator by randomly selecting people and asking them to do something on your calculator (which has a special timer to record how long the enter button is pressed). You practiced on the people at work and found a standard deviation of about 0.15 seconds. You want to get a 88% confidence interval that is only 0.02 in width. How many people do you need to have in your study?

Q: A 93.32% Cl is given as (2.5, 3.5). From this information, find a 95% confidence interval (yes, this…

A: The provided information is as follows:The 93.32% confidence interval is (2.5,3.5).

Q: (a) What are the null hypothesis Ho and the alternative hypothesis H₁ that should be used for the…

A: Test is that whether the mean SI score has decreased. From previous studies,  the mean is 82.

Q: Imagine you gather a sample of individuals and have them report their GPA. One individual's GPA is…

A:

Q: A random sample of 300 college freshmen found that 112 of them own an iPhone.  Find a 95% confidence…

A: Given, Favorable Cases XX = 112112 Sample Size NN = 300300

Q: Out of a sample of 600 adults aged 18 to 30, 162 still lived with their parents. Based on this,…

A:

Q: I've asked 91 students on Monday whether they did their homework over the weekend. 20 of them said…

A:

Q: f n=450 and X = 360, construct a 99% confidence interval.

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Q: A survey of 1,000 adults showed 58% believed the driving age should be changed from 16 years of age…

A: Provided information: Number of adults in a survey = 1000 58% believed the driving age should be…

Q: There are many reasons adults use credit cards. A recent survey found that 66% of adults used credit…

A: 66% of adults use credit cards for convenience.Confidence level is 99% i.e., 0.99.Margin of error is…

Q: A poll of 1060 adults in a country was conducted by telephone. Of those surveyed, 169 had…

A: The sample size is 1060 and number of success is 169.

Q: Suppose that the a college wants to have an idea of the average SAT score of the incoming freshman…

A: The confidence level is 0.90, the standard deviation is 310 and margin of error E is 50.

Q: You measure 31 dogs' weights, and find they have a mean weight of 73 ounces. Assume the population…

A:

Q: A psychologist is studying smokers' self-images, which she measures using the self-image (SI) score…

A: Since you have posted a question with multiple sub parts, according to our guidelines we can solve…

Q: The number of television sets coming off a production line each day is known to have a standard…

A:

Q: A federal report indicated that 17% of children under age 6 live in poverty in Nevada, an increase…

A: Given data, p=17%=0.17 E=2%=0.02 z-value at 99% confidence is Zc=2.576 n=?

Q: If n=27, (x-bar)=34, and s=3, find the margin of error at a 90% confidence leve Give your answer to…

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Q: A study at Harvard found that 44% of their students binge drink. You are at Princeton doing a…

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Q: A research group asked 4488 Americans how they fall asleep, and 536 of them fall asleep on their…

A: Obtain the 90% confidence interval for the percentage of all Americans who fall asleep on their…

Q: Two friends, Karen and Jodi, work different shifts for the same ambulance service. They wonder if…

A: We have,

Q: one with a 95% confidence level and the other with a 99.7% confidence level. Which interval is…

A: Confidence interval is probability, which refers that population parameter will fall within set of…

Q: Database A contains 40 data items and is made up with an equal number of the values of 0 and 100 and…

A: Measure of central tendency measures the central or average value of a dataset. Measured of…

Q: How much more sensitive to contrast are athletes with eye grease than without eye grease? Give a 95%…

A:

Q: A recent study indicated that 24% of women over 55 are widows. A researcher wishes to estimate with…

A:

Q: If n = 15, the sample mean = 150, SD = 10, what is the confidence interval (using 99% confidence…

A: Given data,n=15x=150σ=10z-value at 99% confidence is Zc=2.576

Q: The owner of a café has recently surveyed a random sample of n = 250 customers of the café. She…

A:

Q: What proportion of Law School applicants are accepted into Law School? In a survey of a random…

A: According to the given information in this question  We can say that the We are 95% confident the…

Q: Test the claim that there is a difference between the mean numbers of calls for the two shifts at…

A: Given that For Karen, sample size n1 = 41, sample mean = 5.1 and population SD = 1.5 For Jodi,…

Q: The police department wants to reduce the margin of error for their 95% confidence interval. If they…

A: Here Given  The police department wants to reduce the margin of error for their 95% confidence…

Q: Of the 1,000 people, 550 people used company s's smartphone and 460 people used company a's…

A: Given: n= 1000 ,x= 550.0 At 95.0 % confidence level , z score= 1.96 Need to find confidence…

Q: You measure 50 turtles' weights, and find they have a mean weight of 76 ounces. Assume the…

A:

Q: Construct a 90% confidence interval for the mean when x̅=50 and there are 31 observations. Suppose…

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Q: This my third time posting the same question. Because no one answer it straight to me. I already…

A: 1)From the provided information, The sample number of students watching video (n) = 19 The number of…

Q: ou are a teacher at a gifted school, and you feel that the newest class of students is even brighter…

A: From the provided information, Population mean (µ) = 127 Sample size (n) = 32 Sample mean (x̅) = 134…

Q: now find the 99% confidence interval given the same information, x=13

A: The given regression equation is y^=7+15x se=10.14X__=7n=22∑Xi-X__2=200

Q: A recent survey conducted in a nearby town showed that 791 out of 1,495 people do most their holiday…

A: Here, the sample proportion is =7911495=0.5291 Now, for 90% confidence z=1.645

Q: The dean randomly selected 33 students who took the calculus final exam and looked at their scores…

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Q: BEING SPECIFIC, what kind of statistical analysis should you perform, and WHY? Three parts of your…

A: Given is the question to decide which statistical should be performed.

Q: Out of 500 people sampled, 145 received flu vaccinations this year. Based on this, construct a 90%…

A: We have given that  Sample size n=500 , favorable cases x=145 90% confidence interval  Sample…

Q: suppose a random sample of 50 basketball players have an average height of 78 inches. Also assume…

A: Solution: Let X be the random variable defined as the height of a basketball player. Sample size: n…

Q: You are comparing men and women on hours spent watching TV. You pick a sample of 12 men and 14 women…

A:

Q: ou measure 32 backpacks' weights, and find they have a mean weight of 79 ounces. Assume the…

A: Solution: Given information: n= 32 Sample size  x= 79 ounces Sample mean σ=10.2 ounces Population…

Q: A psychologist is studying the self image of smokers, as measured by the self-image (SI) score from…

A: The objective of the question is to understand the concepts of null hypothesis, alternative…

Q: If n = 20, the sample mean = 250, SD = 15, SEM = 3.354, what is the confidence interval (using 95%…

A: The formula for a confidence interval for the population mean μ\mu when the population standard…

Q: A Gallup survey of 2324 adults (at least 18 years old) in the U.S. found that 417 of them have…

A: The formula of the confidence interval is,