Mrs Reyes wants to test if her students in Basic Calculus spend less than 30 minutes per day on homework. A random sample of 64 students shows that they spend an average of 24.5 minutes per day on homework. Assume that the population standard deviation is 15.3 minutes and that the test is to be made at the 5% significance level. What is the critical value of z? Round your answers to 3 decimal places.

Q: sample of 36 students to answer the question, “How anxious do you feel when you know you have to do…

A: Given that  Sample size (n) =36 Sample mean (x¯) = 58 Sample Standard deviation (s) = 30 Confidence…

Q: You are conducting an experiment to examine the anxiety levels of a group of Psychology students.…

A:

Q: Are you smarter than a second-grader? A random sample of 62 second-graders in a certain school…

A: GivenMean(x)=57sample size(n)=62standard deviation(σ)=14α=0.10

Q: The percent of fat calories that a person consumes each day is normally distributed with a mean of…

A: Solution: Let X be the average percent of fat calories. From the given information, X follows normal…

Q: A mandatory competency test for high school sophomores has a normal distribution with a mean of…

A: Suppose a random variable X, defines the scores in competency test for high school sophomores.

Q: Carol-Anne is an environmental scientist studying the heights of red oak trees in a nearby marsh and…

A: It is given that the researcher randomly selected 10 red oak trees from each habitat and records the…

Q: A medical lab tested a sample of 8 vials of blood for acidity on the pH scale.  Use this data to…

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Q: The director of research and development is testing a new medicine. She wants to know if there is…

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Q: group of students take a Statistics Exam where the average was M = 85 and the standard deviation was…

A: We have given that  X~N( mu , sigma^2) Mu= 85 ,sigma =6.8 Z-score = (x-mu )/sigma

Q: Amy is studying the amount of sleep that college students get on class-nights. Earlier sleep…

A: Formula for the sample size needed to estimate a population mean is

Q: Use Z scores to compare the given values The tallest living man at one time had a height of 245cm.…

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Q: Use the z table to find the value k so that 40% of the scores are greater than k.

A: Normal distribution is widely used in statistics . It is very useful in modern times .

Q: A study was conducted with a sample of 20 college students to see how many students would have low…

A: Suppose a random variable x defines the bone mineral density of students.

Q: A mandatory competency test for high school sophomores has a normal distribution with a mean of 395…

A:

Q: You are conducting an experiment to examine the anxiety levels of a group of Engineering studer The…

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Q: Brewed decaffeinated coffee contains some caffeine. We want to estimate the amount of caffeine in 8…

A:

Q: You are interested in learning about the average online hours per day for ABC College students. Data…

A: 1.

Q: This year’s group of high school students did poorly on their final exams (M = 69, s = 11.3),…

A: Given information- We have given the mean and standard deviation of the high school students final…

Q: One hundred students took a midterm exam designed to measure knowledge of statistics. Their scores…

A: Solution: Let X be the scores. From the given information, X follows normal distribution with mean…

Q: A psychologist wants to estimate the amount of math anxiety that the population of high school…

A:

Q: mandatory competency test for high school sophomores has a normal distribution with a mean of  425…

A: Given that.   X~N( μ , ?)   μ=425     , ?=83   Z-score =( x - μ )/?

Q: Your instructor wishes to estimate the mean amount of time students spend studying math each…

A: Given that  Margin of error =E =2 Population standard deviation =12.7 95% confidence.

Q: A psychologist wants to estimate the amount of math anxiety that the population of high school…

A: The psychologist wants to estimate the amount of math anxiety that the population of high school…

Q: A medical statistician wants to estimate the average weight loss of people who are on a new diet…

A: Given,standard deviation(σ)=8margin of error(E)=2α=1-0.94=0.06α2=0.03Z0.03=1.8808       (from…

Q: Assume that adults have IQ scores that are normally distributed with a mean of 95.4 and a standard…

A: Let "X" be the IQ score of adults. Draw the normal curve and shade the area of 0.25 to the left…

Q: Assume that adults have IQ scores that are normally distributed with a mean of 95.6 and a standard…

A: Given: x~N(μ,σ)μ=95.6σ=24.3

Q: A group of students take a Statistics Exam where the average was M = 85 and the standard deviation…

A: The Normal distribution is also called as the Gaussian distribution. It is the most common…

Q: A mandatory competency test for high school sophomores has a normal distribution with a mean of 410…

A:

Q: Are you smarter than a second-grader? A random sample of 55 second-graders in a certain school…

A: Given that  Hypothesized Population Mean (\mu)(μ) = 5151 Population Standard Deviation…

Q: Test scores for the SAT are close to normal with an average of 850 and a standard deviation of 100.…

A: Given information: Mean SAT test scores μ=850 Standard deviation of SAT test scores σ=100 The SAT…

Q: Assume that adults have iq scores that are normally distributed with a mean of 98.2 and a standard…

A:

Q: Scenario 3: On an examination given to students at a large number of different schools, the mean…

A: Formula

Q: The director of research and development is testing a new medicine. She wants to know if there is…

A: From the provided information, Sample size (n) = 86 Sample mean (x̅) = 332 Population standard…

Q: A psychologist wants to estimate the amount of math anxiety that the population of high school…

A:

Q: Researchers want to estimate the IQ scores for 3 year old children. It is known from a previous…

A: Given:

Q: you created a survey that measue Depression In you want to test people. the Claim that the mean.…

A: Solution-: Given: x¯=6.7,μ0=6.5,n=145,s=1.5 We test the claim that the mean measurement of…

Q: the golf scores for a school team were normally with a mean of 68 and a standard deviation of 3. Use…

A:

Q: The mean is 146 and the standard deviation is 35. A score of 41 is how many z-scores below the mean?

A:

Q: A psychologist created a questionnaire to assess people's aggression. Assume that the questionnaire…

A: Given: A psychologist created a questionnaire to assess people's aggression. The questionnaire…

Q: Find the z-score when x is 5, mean equals 7, and standard deviation 3.

A: Solution: Let X be the random variable. Then, the z-score is calculated by using the formula

Q: A medical statistician wants to estimate the average weight loss of people who are on a new diet…

A: Given Data: ME=4/2=2 σ=8   z-value corresponding to 97% of CI=2.17