Answer: The boy sold 26 bags of butter popcorn and 14 bags of caramel popcorn.
Step-by-step explanation: Given that the boy scouts are selling two types of popcorn as part of a fundraiser, butter and caramel.
Butter popcorn sells for $5 per bag and caramel popcorn sells for $6.50 per bag. Till now, Alec has sold 40 total bags and raised $221.
We are to find the number of bags he has sold for each type of popcorn.
Let a and b represents the number of bags of butter popcorn and caramel popcorn that the boy sold.
Then, according to the given information, we have

Multiplying equation (i) by 5, we have

Subtracting equation (iii) from equation (ii), we get

From equation (i), we get

Thus, the boy sold 26 bags of butter popcorn and 14 bags of caramel popcorn.