Question

(I have a deadline in 3 hours :c ) Ann's Coffee Shop makes a blend that is a mixture of two types of coffee. Type A coffee costs Ann $4.35 per pound, and type B coffee costs $5.40 per pound. This month's blend used three times as many pounds of type B coffee as type A, for a total cost of $780.90. How many pounds of type A coffee were used?

Answer 1

The two equations would be: 4.35a + 5.40b = 780.90 and b = 3a substitute: 4.35a + 5.40(3a) = 780.90 Multiply: 4.35a + 16.2a = 780.90 add like terms: 20.55a = 780.9 divide by 20.55: a = 38 substitute into the other equation: b = 3(38) multiply: b = 114 This means that 38 pounds of coffee were used for type A (variable a) and 114 pounds of coffee were used for type B (variable b)

Answer 2

A=3B
4.35A+5.40B=780.95
Substitute 3B into A for the second equation:
4.35(3B)+5.40B=780.90
13.05B+5.40B=780.90
18.45B=780.90
B=42.33
Plug into equation 1:
A=3B
A=3(42.33)
A=126.98