Question 121454
At Gwen's garage sale, all books were one price, and all magazines were another price. harriet bought four books and three magazines for $1.45 and June bought two books and five magazines for $1.25. What was the price of a book and what was the price for a magazine?<br><br>

This problem is solved using a system of linear equations using eliminaiton.  First off we need to set up the variables.<br>

x = price of each book
y = price of each magazine<br>

now we set up our system<br>

4x + 3y = 1.45
2x + 5y = 1.25<br>

now we multiply by 100 to clear the decimals<br>

400x + 300y = 145
200x + 500y = 125<br>

Now multiply the second equation by -2.<br>

-400x - 1000y = -250<br>

Now add the first equation to that and cancel the x's and solve for y.<br>

400x + 300y = 145
-400x - 1000y = -250
---------------------
-700y = -105
y = 0.15<br>

now plug that into the first equation and solve for x.<br>

400x + 300(0.15) = 145
400x + 45 = 145
400x = 100
x = 0.25<br>

So each book is priced at 25 cents and each magazine is priced at 15 cents.