Answer:
Part A. The girls have 7/8 pizza all together.
Part B. Samantha drank 5/10 or 1/2 water that day.
Explanation:
Part A. The answer is 7/8 because 2/4 is the same thing as 4/8.
2/4 = 4/8
4/8 + 3/8 = 7/8.
So, for the first question the answer is 7/8.
Part B. The answer is 5/10 because 1/5 = 2/10
1/5 = 2/10
2/10 + 3/10 = 5/10
Hope this helps! :)