The school had a bake sale to raise
money. A group of 11 students bought
either chocolate chip cookies for $.40
each or brownies for $.50 each. The total
amount they spent was $5.10. How
many chocolate chip cookies and
brownies did they buy?
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To solve this problem, we can use a system of equations. Let's assign variables to represent the number of chocolate chip cookies and brownies bought.
Let's say x represents the number of chocolate chip cookies, and y represents the number of brownies.
Given the information in the problem, we can form two equations based on the total amount spent and the number of items bought:
Equation 1: 0.40x + 0.50y = 5.10
This equation represents the total amount spent on cookies and brownies.
Equation 2: x + y = 11
This equation represents the total number of items bought.
Now, we can solve this system of equations.
To do this, we can use a method called substitution or elimination.
Let's use the elimination method.
Multiply both sides of Equation 2 by 0.40 (since it has x as a coefficient) to match the coefficients of x in both equations:
0.40(x + y) = 0.40(11)
0.40x + 0.40y = 4.40
Now, we can subtract Equation 1 from the modified Equation 2:
(0.40x + 0.40y) - (0.40x + 0.50y) = 4.40 - 5.10
Simplifying this equation:
0.40x + 0.40y - 0.40x - 0.50y = -0.70
0.10y = -0.70
Divide both sides of the equation by 0.10:
y = -0.70 / 0.10
y = -7
Since the number of brownies cannot be negative, there seems to be an error in the problem statement.
Please double-check the given information or rephrase the question.