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Please help to find the correct EXCEL FORMULA toanswer the following.t-value?margin of error without using confidence. t?upper bound confidence interval?lower bound confidence interval?please ma1 The Sweet Feed Company sells lizard food in large-sized bags that are weighed on an old scale. A random sample of lizard food 2 bags is selected and weighed precisely on a laboratory scale. The data

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Final answer:

To calculate the confidence interval for a population mean, you can use the formula (lower bound, upper bound) = (point estimate - EBM, point estimate + EBM), where EBM represents the margin of error. The degrees of freedom can be calculated by subtracting 1 from the sample size. The appropriate t value to use for a two-tailed 95 percent confidence interval can be found using a t-distribution table or calculator. The 95 percent confidence interval can then be calculated using the formula mentioned above. Similarly, the 99 percent confidence interval can be calculated using a different t value. If the sample size is different, the t value and resulting confidence interval will also change.

Step-by-step explanation:

The formula for calculating a confidence interval for a population mean, when the population standard deviation is unknown, is:

(lower bound, upper bound) = (point estimate - EBM, point estimate + EBM)

  1. To find the degrees of freedom (df), subtract 1 from the sample size (n). In this case, since the sample size is 20, the degrees of freedom would be 19.
  2. For a two-tailed 95 percent confidence interval, the appropriate t value to use in the formula is 2.093.
  3. To calculate the 95 percent confidence interval, you would use the formula mentioned above.
  4. To calculate the 99 percent confidence interval, you would use the same formula but with a different t value. For a two-tailed 99 percent confidence interval with 19 degrees of freedom, the t value is 2.861.
  5. If the sample size was 30 instead of 20, the 95 percent confidence interval can be calculated using the same formula, but the t value would be 2.042.

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