Question

at a local book store, fiction books were on sale. Some were priced at $6 and some at $8. Marci bought 10 books and spent a total of $68.00. How many $6 books did she buy?​

Answer 1

6 $6 books

Explanation:

Using the information, we can create a system of equations.

We can let x represent the total number of $6 Marci bought and y represent the total number of $8 books she bought.

Because the total number of books is 10, one equation we have is x + y = 10.

Because the total cost of both types of books is $68, our other equation is 6x + 8y = 68.

We can solve with substitution by isolating y in the first equation and plugging it into the second equation:

`x+y=10\\y=-x+10\\\\6x+8(-x+10)=68\\6x-8x+80=68\\-2x+80=68\\-2x=-12\\x=6`

Thus, the total number of $6 books Marci bought was 6.