Final answer:
The algebraic expression representing the number of oranges given to the adults in the group is 2n - 5, after accounting for the 5 oranges remaining in the box.
Step-by-step explanation:
To find the algebraic expression for the number of oranges given to the adults in the group, we can set up a simple model based on the conditions described in the question. Since n oranges are distributed and each adult gets 2 oranges, we would usually multiply the number of adults by 2 to get the total number of oranges that adults received. However, since there are 5 oranges left in the box after distribution, we must account for them by subtracting those 5 from the total number of oranges n. Thus, the algebraic expression for the number of oranges given to the adults is 2n - 5.