Answer: option C is the correct answer.
Step-by-step explanation:
Let x represent the number of apples in the first box.
Let y represent the number of apples in the second box.
Two boxes of apples contain a total of 24 apples. It means that
x + y = 24
If you halve the number of apples in the first box and add 4 apples to the second box, the total changes to 20 apples. This means that
x/2 + y + 4 = 20
Cross multiplying by 2, it becomes
x + 2y + 8 = 40
x + 2y = 40 - 8
x + 2y = 32- - - - - - - - - - - - - -1
Substituting x = 24 - y into equation 1, it becomes
24 - y + 2y = 32
- y + 2y = 32 - 24
y = 8
x = 24 - y = 24 - 8
x = 16