You are a researcher studying the lifespan of a certain species of bacteria. A preliminary sample of 25 bacteria reveals a sample mean of ī = 78 hours. It is known that lifespans have standard deviation of o = 4.6 hours. You would like to estimate the mean lifespan for this species of bacteria to within a margin of error of 0.55 hours at a 90% level of confidence. What sample size should you gather to achieve a 0.55 hour margin of error? Round your answer up to the nearest whole number. bacteria

You are a researcher studying the lifespan of a certain species of bacteria. A preliminary sample of 25 bacteria reveals a sample mean of ī = 78 hours. It is known that lifespans have standard deviation of o = 4.6 hours. You would like to estimate the mean lifespan for this species of bacteria to within a margin of error of 0.55 hours at a 90% level of confidence. What sample size should you gather to achieve a 0.55 hour margin of error? Round your answer up to the nearest whole number. bacteria

A First Course in Probability (10th Edition)

10th Edition

ISBN:9780134753119

Author:Sheldon Ross

Publisher:Sheldon Ross

Chapter1: Combinatorial Analysis

Section: Chapter Questions

Problem 1.1P: a. How many different 7-place license plates are possible if the first 2 places are for letters and...

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A researcher studying the lifespan of a certain species of bacteria. A preliminary sample of 30 bacteria reveals a sample mean of ¯x=68x¯=68 hours with a standard deviation of s=7s=7 hours. He would like to estimate the mean lifespan for this species of bacteria to within a margin of error of 0.75 hours at a 99% level of confidence.What sample size should you gather to achieve a 0.75 hour margin of error?He would need to sample bacteria.
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You are a researcher studying the lifespan of a certain species of bacteria. A preliminary sample of 35 bacteria reveals a sample mean of ¯x=76x¯=76 hours. The population standard deviation is known to be 5.6 hours. You would like to estimate the mean lifespan for this species of bacteria to within a margin of error of 0.4 hours at a 90% level of confidence. How many more bacteria should you sample to achieve a 0.4 hour margin of error? n = bacteria
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Yane is a researcher who studies bacteria. They are trying to ascertain the mean lifespan for a bacteria species. It is believed that the standard deviation of their lifespan is o = 4 hours. They would like to estimate the mean lifespan for this species of bacteria to within a margin of error of 0.45 hours at a 99% level of confidence. What sample size should they gather to achieve this? Remember your answer must be a whole number. n= bacteria
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