Let x be the number of students tickets and y be the number of adult tickets,
equation 1. 12x + 16y = $3700
equation 2. x + y = 250
In equation 2, x= 250-y — equation 3
Put equation 3 into 1,
12(250-y) + 16y = $3700
3000 - 12y + 16y = $3700
4y = $700
y = 175
Sub y = $175 into equation 2
x + 175 = 250
x = 75
The number of students ticket sold is 75 and the number of adult ticket sold is 175.