Students in statistics class are conducting survey to estimate the mean number of units students at their college are enrolled in. The students collect random sample of 49 students. The mean of the sample is 12.2 units. The standard deviation is 1.6 units. What is the 95% confidence interval for the number of units students in their college are enrolled in? Assume that the distribution of individual student enrollment units at this college is approximately normal: (10.2 14.2) (12.0 12.4) (9.0 15.4) (11.7,12.7) No confidence interval can be constructed since the conditions for T-interval are not met.
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Since the confidence level is 95%, the alpha value is 1 - 0.95 = 0.05. This means the confidence value is the t-score for a 95% confidence level, which corresponds to t sub 0.025 with 48 degrees of freedom. Using a t-table or calculator, we find that t sub 0.025 Show more…
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Students in a statistics class are conducting a survey to estimate the mean number of units students at their college are enrolled in. The students collect a random sample of 49 students. The mean of the sample is 12.2 units. The sample has a standard deviation is 1.6 units. What is the 95% confidence interval for the number of units students in their coll Assume that the distribution of individual student enrollment units at this college normal.
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Students in a statistics class are conducting a survey to estimate the mean number of units students at their college are enrolled in. The students collect a random sample of 49 students. The mean of the sample is 12.2 units. The sample has a standard deviation is 1.6 units. What is the 95% confidence interval for the number of units students in their college are enrolled in? Assume that the distribution of individual student enrollment units at this college is approximately normal. (10.2 , 14.2) (12.0 , 12.4) (9.0 , 15.4) (11.7 , 12.7) No confidence interval can be constructed since the conditions for a T-interval are not met. 2. A group of engineers developed a new design for a steel cable. They need to estimate the amount of weight the cable can hold. The weight limit will be reported on cable packaging. The engineers take a random sample of 46 cables and apply weights to each of them until they break. The 46 cables have a mean breaking weight of 779 lb. The standard deviation of the breaking weight for the sample is 15.4 lb. Find the 99% confidence interval to estimate the mean breaking weight for this type cable. ( , ) Your answer should be to 2 decimal places.
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