.
Let "C" be the number of children.
Then the total revenue equation is
12*(600-C) + 9C = 6720 dollars.
Express "C" and calculate
C = = 160. ANSWER
CHECK. 9*160 + (600-160)*12 = 6720 dollars. ! Correct !
Solved.
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It is a standard tickets problem.
There are different methods of solving such problems.
Read the lessons
- Using systems of equations to solve problems on tickets
- Three methods for solving standard (typical) problems on tickets
in this site.
From these lessons, learn on how to solve such problems once and for all.
Also, you have this free of charge online textbook in ALGEBRA-I in this site
- ALGEBRA-I - YOUR ONLINE TEXTBOOK.
The referred lessons are the part of this online textbook under the topic "Systems of two linear equations in two unknowns".
Save the link to this online textbook together with its description
Free of charge online textbook in ALGEBRA-I
https://www.algebra.com/algebra/homework/quadratic/lessons/ALGEBRA-I-YOUR-ONLINE-TEXTBOOK.lesson
to your archive and use it when it is needed.