Answer:
3
Explanation:
Total number of students = 9
Admision ticket cost = $10
Let cost of special exhibit ticket cost x
2 students ecah bought 4x
7 students each bought 3x
Admission. Cost + exhibit ticket cost = total cost
(10 * 9) + (2 * 4x) + (7 * 3x) = 177
90 + 8x + 21x = 177
29x = 177 - 90
29x = 87
x = $3