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 = 80 hours with a standard deviation of s = 5.4 hours. You would like to estimate the mean lifespan for this species of bacteria to within a margin of error of 0.65 hours at a 90% level of confidence. What sample size should you gather to achieve a 0.65 hour margin of error? Round your answer up to the nearest whole number
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We are given the sample mean (x̄ = 80 hours), the sample standard deviation (s = 5.4 hours), the desired margin of error (E = 0.65 hours), and the confidence level (90%). Show more…
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