To prevent E. coli, meat should be cooked to an internaltemperature of at least 160°F. However, different meat pattiescooked for the same amount of time will have different finalinternal temperatures because of variations in the patties andvariations in burner temperatures. A regional hamburger chain plansto replace its current burners with one of two new digitallycontrolled models. If there is a significant difference in thevariance of the two models, the chain will select the model withthe smaller variance in the final internal meat temperature. Thechain's purchasing directors have arranged to randomly sample 11patties cooked by burner model 1 and 13 cooked by burner model 2.The final internal temperature of the patties cooked on each burnerare in cells F117 to G130 on the answers sheet.
- Perform a hypothesis test at the 10% significance level to seewhether there is a significant difference between the variances ofthe two burner models.
DATA:
| Model 1 | Model 2 |
| 1 | 180.0 | 178.6 |
| 2 | 181.5 | 182.3 |
| 3 | 178.9 | 177.5 |
| 4 | 176.4 | 180.6 |
| 5 | 180.7 | 178.3 |
| 6 | 181.0 | 180.7 |
| 7 | 180.3 | 181.4 |
| 8 | 184.6 | 180.5 |
| 9 | 185.6 | 179.6 |
| 10 | 179.7 | 178.2 |
| 11 | 178.9 | 182.0 |
| 12 | | 181.5 |
| 13 | | 180.8 |
| | |
ANSWER MUST FOLLOW THIS FORMAT:
| Define H0 : | |
| Define H1 : | |
| Test statistic | |
| Critical value of test statistic | |
| Decision rule | |
| Calculated value of test statistic | |
| Reject or fail to reject H0? | |
| Can we conclude the population variances are equal? | |
