Question 822256: [ There are 80 quarters and nickels in a jar. The total value is $14.60. How many of each type of coin is there? ] Found 2 solutions by stanbon, TimothyLamb:Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website! Hi. I'm trying to solve one of those coin problems that go there are 80 coins in a jar. They are either quarters or nickels. The total value is 14.60. How many of each type of coin is there?
Well I thought it would be a good idea to set up a system of linear equations such as
x+y=80
25x+5y=14.60
---------------------
Comment::
Your last equation says cents + cents = dollars.
You need it to say cents + cents = cents
25x + 5y = 1460 cents
-----------------------------
Try that Please.
Cheers,
Stan H.
================
You can put this solution on YOUR website! ---
x + y = 80
5x + 25y = 1460
---
first, solve by matrix method:
---
copy and paste the above standard form linear equations in to this solver:
https://sooeet.com/math/system-of-linear-equations-solver.php
---
answer:
x= nickels = 27
y= quarters = 53
---
now solve by elimination, to check the answer:
---
-5x - 5y = -400
5x + 25y = 1460
---
add:
20y = 1060
---
answer (same as the matrix method answer):
x = nickels = 27
y = quarters = 53
---
Solve and graph linear equations:
https://sooeet.com/math/linear-equation-solver.php
---
Solve quadratic equations, quadratic formula:
https://sooeet.com/math/quadratic-formula-solver.php
---
Solve systems of linear equations up to 6-equations 6-variables:
https://sooeet.com/math/system-of-linear-equations-solver.php
(