Solve thes problem - Speech or Presentation Example

From a table, the probability of a value being to the left or equal to this z-score is .8962; so the probability to be to the right of z = 1.2649 (or to the left of z = -1.2649) is: For 99% confidence intervals, 99% of the area under the curve will be shaded when the endpoints are 2.5758 standard deviations away from the mean. The endpoints for this confidence interval are found by: Adding a sample size m = 75, find the sample mean (m2) of the added sample that would lead to a p-value > 0.05 for the combined sample.

Find the probability of obtaining a sample mean from the added sample within the needed range. To calculate the probability that Type 1 error occurs, we want to calculate what is the probability that the null hypothesis is correct ( the p-value is greater than .05 significance level) and the mean of the sample is in one of the tail ends < 8 or > 12. This would result in an interval (6.9 to 13.1). The probability that there is a Type 1 error when the original rejection criteria is used: mean < 8 or > 12, is the probability that the mean falls within the intervals 6.

9 to 8 and 12 to