Question

When bonding teeth, orthodontists must maintain a dry field. A new bonding adhesive (called "Smartbond") has been developed to eliminate the necessity of a dry field. However, there is concern that the new bonding adhesive is not as strong as the current standard, a composite adhesive. Tests on a sample of 10 extracted teeth bonded with the new adhesive resulted in a mean breaking strength (after 24 hours) of x-5.07 Mpa and a standard deviation of s .46 Mpa where Mpa- megapascal, a measurement of force per unit area. Orthodontists want to know if the true mean breaking strength of the new bonding adhesive is less than 5.70 Mpa, the mean breaking strength of the composite adhesive. Conduct the appropriate analysis for the orthodontists. Use F.01 1. Define the null and alternative hypotheses for the test. 2. Interpret the confidence level of.01 3. Determine the Test Statistic, 4. Determine the Critical Statistic and illustrate the rejection region in /21 (51 12/ a diagram 5. Interpret the findings.

Answer 1