HW IZ Score: 22/175 3/13 answered Question 9 < > Score on last try: 5 of 15 pts. See Details for more. > Next question You can retry this question below Let X be a random variable that represents the weights in pounds (lb) of adult females who are in their 40s. X has mean $\mu = 137$ lbs and standard deviation $\sigma = 5$ lbs. An adult female in her 40s that weighs above 138.75 is considered overweight. A) Is a sample of size 30 or more required to obtain a normally distributed sampling distribution of mean weights? O No Yes B) What is the probability that 36 adult females in their 40s have a mean weight over 138.75 lbs? (Round $\sigma_{\bar{x}}$ to two decimal places and your answer to four decimal places.) **Notes: Round all z-scores to 2 decimal places. Question Help: ? Message instructor Submit Question
Added by Andrea A.
Close
Step 1
A general rule of thumb is that a sample size of 30 or more is sufficient to ensure that the sampling distribution is approximately normal. Show more…
Show all steps
Your feedback will help us improve your experience
Shaiju T and 54 other Intro Stats / AP Statistics educators are ready to help you.
Ask a new question
Labs
Want to see this concept in action?
Explore this concept interactively to see how it behaves as you change inputs.
Key Concepts
Recommended Videos
Assume that women's weights are normally distributed with a mean of 143 pounds and a standard deviation of 29 pounds (based on data from the National Health Survey). If a woman is randomly selected, find the probability that her weight is between 150 pounds and 180 pounds. Round to 4 decimal places.
Shaiju T.
If the average BMI of adults in country A is 20 with a standard deviation of 3, what is the probability that the mean of random sample of 36 adults selected from country A is less than 21? (Assume that the BMI is normally distributed.) A. 0.341 B. 0.477 C. 0.977 D. 0.159 E. 0.382 A research wishes to know whether the average weight gain from a certain diet program is greater than 4 lb in a month for a particular population of men weight between 130 lbs to 140 lbs. A random sample of 5 subjects selected from this population and went through this diet program and the weight gain (in pounds) data is the followings: 2.2 4.5 1.9 3.1 2.4. Which of the followings is the correct conclusion when using the t-test to test if the average weight gain is greater than 4 lb using the data values above? A. None of the above B. Right-tailed test C. Two-tailed test D. Left-tailed test A research wishes to know whether the average weight gain from a certain diet program is greater than 4 lb in a month for a particular population of men weight between 130 lbs to 140 lbs. A random sample of 5 subjects selected from this population and went through this diet program and the weight gain (in pounds) data is the followings: 2.2 4.5 1.9 3.1 2.4. What is the p-value when using the t-test to test if the average weight gain is greater than 4 lb using the data values above? (Round the answer to the 3rd decimal place. For instance, if the value is 0.00237, then write 0.002.)
Clarissa B.
Let X be a random variable that represents the weights in pounds (lb) of adult males who are in their 40s. X has a normal distribution with mean μ = 168 lbs and standard deviation σ = 5 lbs. An adult male in his 40s that weighs above 170.5 is considered overweight. A) What is the probability that one adult male in his 40s is overweight? (Round your answer to four decimal places.) B) What is the probability that 24 adult males in their 40s have a mean weight over 170.5 lbs? (Round σ_x̄ to two decimal places and your answer to four decimal places.) C) What is the probability that 35 adult males in their 40s have a mean weight over 170.5 lbs? (Round σ_x̄ to two decimal places and your answer to four decimal places.) D) This sampling distribution problem requires the sample size to be greater than or equal 30. True False
Farruh T.
Recommended Textbooks
Elementary Statistics a Step by Step Approach
The Practice of Statistics for AP
Introductory Statistics
Transcript
18,000,000+
Students on Numerade
Trusted by students at 8,000+ universities
Watch the video solution with this free unlock.
EMAIL
PASSWORD