Final answer:
To find out how many people in the group are 12 years old or older, we can set up a system of equations using the given information. Solving these equations simultaneously, we can find the values of x and y. Therefore, there are 2 people in the group who are 12 years old or older.
Step-by-step explanation:
To find out how many people in the group are 12 years old or older, we can set up a system of equations using the given information. Let's assume that x represents the number of people who are 12 years old or older, and y represents the number of people who are 11 years old or younger. We can then set up the following two equations:
- x + y = 5 (since there are a total of 5 people in the group)
- 8x + 5y = 31 (since the total cost of the tickets is $31)
Solving these equations simultaneously, we can find the values of x and y:
- Multiplying the first equation by 8, we get 8x + 8y = 40
- Subtracting the second equation from this new equation, we get 8y - 5y = 40 - 31
- Simplifying, we get 3y = 9
- Dividing both sides by 3, we get y = 3
- Substituting this value of y into the first equation, we get x + 3 = 5
- Subtracting 3 from both sides, we get x = 2
Therefore, there are 2 people in the group who are 12 years old or older.