Step-by-step explanation:
We are given the following;
Sima needs to cook a 7kg turkey.
The instruction says to cook the turkey for 20 minutes for each kg. This means for a 7kg turkey, she should cook for;
![\begin{gathered} 1kg=20\min s \\ 7kg=(20*7) \\ 7kg=140\min s \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/1tfgfoa3ell9er64tce0cik5t7bpo45y14.png)
The cooking instruction further says to add an extra 125 minutes.
This means the turkey would cook for a total of;
![\begin{gathered} Time\text{ per }kg=140\min s \\ \text{Added time}=125\min s \\ \text{Total time}=265\min s \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/fsioghd78fqcxvxuxc39wdg81uxg5k3a6a.png)
We can convert this to hours as follows;
![\begin{gathered} 60\min s=1hr \\ (265\min s)/(60)=(240\min s)4hrs\text{ rem 25 mins} \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/zfi90l7roy0panuobk92vdgrduk0zw2k8w.png)
Therefore, if the turkey starts to cook by 7:00 AM, then 4 hours and 25 minutes later would be;
![7\colon00am+4\text{hrs 25 mins}=11\colon25am](https://img.qammunity.org/2023/formulas/mathematics/college/wth6qqsokx0lkj9o92m4j06dvj4rw1mz65.png)
ANSWER:
If the turkey needs to finish cooking at 11:30 am, then Sima is right by starting at 7:00 am.
The turkey would be ready by 11:25 am which is right on time.