Suppose the sediment density (g/cm) of a randomly selected specimen from a certain region is normally distributed with mean 2.65 and standard deviation 0.85. a. If a random sample of 25 specimens is selected, what is the probability that the sample average sediment density is between 2.48 and 2.82? ANSWER: b. How large a sample size would be required to ensure that the probability in part a. is at least 0.9544?
Added by John M.
Close
Step 1
48 and 2.822 using the formula: z = (x - μ) / σ For 2.48: z1 = (2.48 - 2.65) / 0.85 ≈ -0.2 For 2.822: z2 = (2.822 - 2.65) / 0.85 ≈ 0.2 Now, we need to find the probability between these z-scores. Since the sample size is 25, the standard deviation of the sample Show more…
Show all steps
Your feedback will help us improve your experience
Clarissa Barr and 67 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
Suppose the sediment density (g/cm) of a randomly selected specimen from a certain region is normally distributed with mean 2.65 and standard deviation 0.85. (a) If a random sample of 25 specimens is selected, what is the probability that the sample average sediment density is at most 3.00? Between 2.65 and 3.00? (b) How large a sample size would be required to ensure that the first probability in part (a) is at least 0.99?
Adi S.
Suppose the sediment density (g/cm) of a randomly selected specimen from a certain region is normally distributed with mean 2.65 and standard deviation 0.85. If a random sample of 12 specimens is selected, what is the probability that the sample mean sediment density is at least 2.00 g/cm?
Jeremy G.
Suppose the sediment density (g/cm) of a randomly selected specimen from a certain region is normally distributed with a mean of 2.65 and a standard deviation of .85. a. If a random sample of 25 specimens is selected, what is the probability that the sample average sediment density is more than 2.35?, b. at most 3.0 and c. between 2.35 and 3.00 d. How large a sample would be required to insure that the probability in part a is at least 0.99
Christopher D.
Recommended Textbooks
Elementary Statistics a Step by Step Approach
The Practice of Statistics for AP
Introductory Statistics
18,000,000+
Students on Numerade
Trusted by students at 8,000+ universities
Watch the video solution with this free unlock.
EMAIL
PASSWORD