bob has 60 coins consisting of quarters and dimes. The coins combined value is 9.45. Find out how many are quarters and how many are dimes.

Question

It is a question on real life systems of linear equations

Answer 1

You will need to use two equations and solve for two variables. 

x=number of quarters

y=number of dimes

You know that x+y=60 because he has 60 coins in total. 

You also know that (.25)x+(.10)y=9.45 because quarters are worth $.25 and dimes are worth $.1. 

Then solve for x in the first equation: x=60-y and plug this into x for the second equation. 

 

Now solve for y in the second equation. That will give you the number of dimes. Then plug it back into the first equation to get x, the number of quarters. Plug both your values into both equations to check your work.