.
2.5*A + (112-A)*2.25 = 269.75 ( A = # of adults )
2.5A + 112*2.25 - 2.25A = 269.75
2.5A - 2.25A = 269.75 - 112*2.25
A = = 71.
Answer. 71 adults and 112-71 = 41 child.
Check. 71*2.5 + 41*2.25 = 269.75. ! Correct !
Solved.
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It is standard "ticket" problem.
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 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".