Answer: 4.75hours or 4 3/4 hours.
Explanation:
To solve this problem you must apply the proccedure shown below:
- You know that one hour has sixty minutes:
1 hour=60 minutes.
- Therefore, you must convert 45 minutes to hours, as following:

- Add this result to 4 hours:

- Therefore she can write this as following:
4.75hours or 4 3/4 hours.