Norris May

01/25/2024 · High School

16 The shape of the distribution of the time required to get an oil change at a 15 -minute oil-change facility is skewed right. However, records indicate that the mean time for an oil change is 16.7 mi is 4.4 minutes. Use StatCrunch to complete parts (a) through (c). (a) To compute probabilities regarding the sample mean using the normal model, what size sample would be required? Choose the correct answer. A. The sample size needs to be less than or equal to 30 . B. Any sample size could be used. C. The sample size needs to be greater than or equal to 30 . D. The normal model cannot be used if the shape of the distribution is skewed right. (b) What is the probability that a random sample of \( n=40 \) oil changes results in a sample mean time less than 15 minutes? The probability is approximately (Round to four decimal places as needed.)