Answer:
70 pounds of high-quality coffee bean and 60 pounds of cheaper coffee bean.
Step-by-step explanation:
Total coffee weight = 130 pounds
Blend Cost = $4.73
High quality bean (H) price = $6.00
Cheaper bean (C) price = $3.25
The weight used of both beans must add up to 130 pounds, while the products of each individual quantity by its cost must add to 4.73 multiplied by 130.
[tex]H+C=130\\6.00H + 3.25C= 130* 4.73[/tex]
Multiplying the first equation by -3.25 and adding it to the second one:
[tex]6.00H - 3.25H + 3.25C - 3.25C = (130* 4.73) - (130*3.25)\\2.75H = 192.4\\H = 70\\C = 130 - H = 130 - 70\\C = 60[/tex]
Sarah should use 70 pounds of high-quality coffee bean and 60 pounds of cheaper coffee bean.