Answer:
78 pounds
Step-by-step explanation:
Let's say Yolanda makes a pounds of Type A coffee and b pounds of Type B coffee. Since the total number of pounds is 130, we can write the equation:
a + b = 130
We know the cost of Type A coffee is $5.20/lb and the cost of Type B coffee is $4.05/lb, so since the total cost is $586.30, we can write:
5.20a + 4.05b = 586.30
We can now solve the system of equations:
a + b = 130
5.20a + 4.05b = 586.30
Manipulate the first equation by subtracting b from both sides:
a + b = 130
a = 130 - b
Substitute 130 - b for a in the second equation:
5.20a + 4.05b = 586.30
5.20 * (130 - b) + 4.05b = 586.30
676 - 5.20b + 4.05b = 586.30
Move the terms with b to one side:
1.15b = 89.70
b = 78
Thus, Yolanda used 78 pounds of Type B coffee.
<em>~ an aesthetics lover</em>