Answer:
B. 11
Step-by-step explanation:
Set up a system of equations where a is the number of adults and c is the number of children
a + c = 87
8a + 5c = 468
Solve by substitution by rearranging the first equation, then substituting it in the second equation:
a = 87 - c
Substitute this for a in the second equation, then solve for c:
8(87 - c) + 5c = 468
696 - 8c + 5c = 468
696 - 3c = 468
-3c = -228
c = 76
Then, plug this into the first equation to solve for a:
a + c = 87
a + 76 = 87
a = 11
So, 11 adults attended the carnival.
The correct answer is B, 11
