Final answer:
Alexis spent 2 hours and 45 minutes away from home, which is equivalent to 2.75 hours.
Step-by-step explanation:
To calculate how long Alexis spent away from home, we need to find the difference between the time she left and the time she returned. She left her house at 7:45 p.m. and returned at 10:30 p.m.
First, we'll convert both times to a 24-hour format to make it easier to compute the time difference. The time Alexis left remains the same as 19:45 (since p.m. times are already in the second half of a 24-hour day), and the time she came back is 22:30.
Next, we subtract the time Alexis left from the time she returned:
22:30
-19:45
______
The difference in the minutes column is 30 - 45, which would be negative, so we need to borrow an hour from the hours column.
22:30
-19:45
______
Convert the borrowed hour into 60 minutes and add to the 30 minutes: 60 + 30 = 90 minutes.
21:90
-19:45
______
Now we can subtract the minutes:
90 - 45 = 45 minutes.
And subtract the hours:
21 - 19 = 2 hours.
Therefore, Alexis spent 2 hours and 45 minutes away from home.
To express this time purely in hours, we convert 45 minutes into hours by dividing by 60:
45 minutes ÷ 60 minutes per hour = 0.75 hours.
Adding this to the 2 hours, we find that Alexis was away from home for 2.75 hours.