Question 215856
Thirty students bought pennants for the football game.  Plain pennants cost $4 each and fancy ones cost $8 each.  If the total bill was $168, how many students bought the fancy pennants?


Step 1. Let x be the number of fancy pennants bought by students.


Step 2. Let 30-x be the number of plain pennants bought by students.


Step 3. Let 8x be the dollar value of the fancy pennants bought by students.


Step 4. Let 4(30-x) be the dollar value of the fancy pennants bought by students.


Step 5.  Total cost is then {{{8x+4(30-x)=168}}} as given by the problem statement.  The following steps will solve this equation:


*[invoke explain_simplification "8x+4(30-x)=168" ]


With x=12, then 30-x=18 


Check total cost if true...8*12+4*18=96+72=168...which is a true statement


Step 6.  ANSWER:  12 students bought the fancy pennants.


I hope the above steps were helpful.


For FREE Step-By-Step videos in Introduction to Algebra, please visit http://www.FreedomUniversity.TV/courses/IntroAlgebra and for Trigonometry visit http://www.FreedomUniversity.TV/courses/Trigonometry.


Good luck in your studies!


Respectfully,
Dr J