Answer:
20 lb
Explanation:
Amount and cost of coffee A:
Let x = number of pounds of coffee A.
The cost of coffee A used is 5.7x.
Amount and cost of coffee B:
"This month's blend used three times as many pounds of type B coffee as type A"
The amount of coffee B used was 3x.
The cost of coffee B used is 4.4(3x) = 13.2x
The total cost is 5.7x + 13.2x. The total cost is $378.00.
5.7x + 13.2x = 378
18.9x = 378
x = 20
Answer: 20 lb of coffee A were used.
Check:
Since 20 lb of coffee A were used, then 60 lb of coffee B were used.
20 lb * $5.70/lb + 60 lb * $4.40/lb = $114 + $264 = $378
We get the correct total of $378, so our calculations are correct.