Question 215018
You have 15 coins in your pocket that are either quarters or nickles. the total $2.75. how many of each coin do you have?


Step 1. Let x be the number of quarters and 15-x be the number of nickles.


Step 2. Let 0.25x be the cost for x number of quarters.


Step 3. Let 0.05(15-x) be the cost for 15-x number of nickles.


Step 4.  0.25x+0.05(15-x)=2.75  where we added Steps 1 and 2.


Step 5.  The following will solve the equation in Step 4.


*[invoke explain_simplification "0.25x+0.05(15-x)=2.75" ]


With x=10, then 10-x=5.  Let's check total value 0.25*10+0.05*5=2.50+0.25=2.70 ...so it checks out.


Step 6.  ANSWER.  The number of quarters is 10 and the number of nickels is 5.


I hope the above steps were helpful. 


For free Step-By-Step Videos on Introduction to Algebra, please visit http://www.FreedomUniversity.TV/courses/IntroAlgebra or for Trigonometry visit http://www.FreedomUniversity.TV/courses/Trigonometry.


And good luck in your studies!


Respectfully,
Dr J