To solve this problem, let's use a system of equations. We'll define the variables and form equations based on the information provided:

Step 1: Define variables

Let:

• $x$ = the number of cookies sold
• $y$ = the number of brownies sold

Step 2: Set up equations based on the given information

We have two pieces of information:

1. Max sold a total of 10 baked goods: $x + y = 10$

2. The total earnings from the sale were $20, with cookies sold at $1.25 each and brownies at $2.50 each: $1.25x + 2.50y = 20$

Step 3: Solve the system of equations

First, let's solve the first equation for $x$: $x = 10 - y$

Substituting $x$ in the second equation: $1.25(10 - y) + 2.50y = 20$ Expanding this: $12.5 - 1.25y + 2.50y = 20$ $1.25y + 12.5 = 20$ $1.25y = 7.5$ $y = 6$

Substituting $y = 6$ back into $x + y = 10$: $x + 6 = 10$ $x = 4$

Solution

Max sold 4 cookies and 6 brownies.

The correct answer is C: 4 cookies and 6 brownies.

Would you like more details or have any questions?

Here are 5 related questions:

1. What would happen if Max sold only brownies, how many would he need to sell to make $20?
2. If cookies were priced at $1.50 each instead of $1.25, how many cookies and brownies would he have sold?
3. How much profit did Max make per cookie if his cost per cookie was $0.75?
4. What would be the new total if Max sold 12 items, maintaining the same price for cookies and brownies?
5. If he sold an equal number of cookies and brownies, how much money would he have made?

Tip:

When solving systems of equations, substitution is useful when one equation can be easily solved for one variable, while elimination works well when both equations are more complex.