Answer:
94 children, 64 students, and 47 adults attended the movie theater. 
Explanation:
Let; a be for adults, s for students, and c for children. 
Make a system to solve for the amount of people. 
c/a = 2 
a + 2a + s = 205 
3a + s = 205 
Simplify. 
s = 205 - 3a 
s = 205 - 3a 
c = 2a 
Plug it in. 
5c + 7s + 12a = 1482 
10a + 7(205 -3a) + 12a = 1482 
10a + 1435 - 21a + 12a = 1482 
a + 1435 = 1482 
a = 47 
Substitute. 
c = 2(47) 
c = 94 
Solve. 
s = 205 - 3(47) 
s = 64