.
We assume that all 291 tickets are sold.
Let "a" be the number of adults; then the number of children is (2a).
The number of students is the rest, (291-a-2a) = 291-3a.
The "money" equation is
12a + 5*(2a) + 7*(291-3a) = 2116 dollars.
Simplify and solve for "a".
12a + 10a + 7*207 - 21a = 2116 - 7*291,
a = 79.
ANSWER. 79 adults; 2*79 = 158 children and (291-3*79) = 54 students.
CHECK. 79*12 + 5*158 + 54*7 = 2116 dollars, total revenue. ! Correct !
Solved.
--------------
This problem is to be solved using one equation in one unknown.
If you want to see many other similar solved problems, look into the lessons
- Advanced word problems to solve using a single linear equation
- HOW TO algebreze and solve these problems using one equation in one unknown
in this site.