Answer:she used 99 pounds of type B coffee.
Step-by-step explanation:
Let x represent the number of pounds of type A coffee that she used.
Let y represent the number of pounds of type B coffee that she used.
Rita made 177 pounds of the blend. This means that
x + y = 177
Type A coffee costs Rita $5.70 per pound, and type B coffee costs $4.10 per pound. This month, the total cost of coffee that she made was $850.50. It means that
5.7x + 4.1y = 850.50 - - - - - - - - - - -1
Substituting x = 177 - y into equation 1, it becomes
5.7(177 - y) + 4.1y = 850.50
1008.9 - 5.7y + 4.1y = 850.5
- 5.7y + 4.1y = 850.5 - 1008.9
- 1.6y = - 158.4
y = - 158.4/ - 1.6
y = 99
Substituting y = 99 into x = 177 - y, it becomes
x = 177 - 99 = 78
