Final answer:
Charlotte watched 1/4 of the movie in the morning and had 1/3 left at the end of the day. After finding a common denominator, we can determine that she watched 5/12 of the movie at night.
Step-by-step explanation:
To determine how much of the movie Charlotte watched at night, we need to consider the total amount of the movie she had watched by the end of the day. Charlotte watched 1/4 of the movie in the morning and had 1/3 of the movie left to watch at the end of the day. To find out how much she watched at night, we subtract the portion watched in the morning and the portion left from the whole movie:
Total movie = 1
Portion watched in the morning + Portion watched at night + Portion left = Total movie
1/4 + Portion watched at night + 1/3 = 1
Now we need to solve for the portion watched at night:
Portion watched at night = 1 - (1/4 + 1/3)
To calculate this, we need a common denominator, which will be 12:
Portion watched at night = 1 - (3/12 + 4/12)
Portion watched at night = 1 - 7/12
Portion watched at night = 12/12 - 7/12
Portion watched at night = 5/12
Therefore, Charlotte watched 5/12 of the movie at night.