The daily electrical energy consumption (in Watts) during July for a random sample of 16 households was recorded. The mean was 3307 W and the standard deviation was 327 W. Assume the underlying distribution of the consumption is normal. Find the lower confidence limit (LCL) of the 95% confidence interval for the mean daily electrical energy consumption during that month. Round your answer to the nearest whole number (integer).
1: The daily electrical energy consumption (in Watts) during July for a random sample of 16 households was recorded. The mean was 3307 W and the standard deviation was 327 W. Assume the underlying distribution of the consumption is normal. Find the lower confidence limit (LCL) of the 95% confidence interval for the mean daily electrical energy consumption during that month. Round your answer to the nearest whole number (integer).
2: The daily electrical energy consumption (in Watts) during July for a random sample of 49 households was recorded. The mean was 4377 W and the standard deviation was 335 W. Find the upper confidence limit (UCL) of the 95% confidence interval for the mean daily electrical energy consumption during that month. Round your answer to the nearest whole number (integer).
3: The time spent, in minutes, on physical activities per day was recorded for a sample of college students. The 90% and 99% confidence intervals for the mean time spent on physical activities are (56.026, 59.974) and (54.909, 61.091). Which of the following would be a 95% confidence interval calculated from the sample data used to create the confidence intervals above?
4:
Which of the following statements is NOT true with respect to the t distribution?
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The exact shape of the t distribution depends on the number of degrees of freedom. |
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The t distribution is symmetrical. |
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The t distribution is more spread out than the standard |
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The t distribution is less spread out than the standard normal distribution. |
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