Ryan's Coffee Shop makes a blend that is a mixture of two types of coffee. Type A coffee costs Ryan $5.70 per pound, and type B coffee costs $4.40 per pound. This month's blend used three times as many pounds of type B coffee as type A, for a total cost of $378.00. How many pounds of type A coffee were used?

20 lb

Step-by-step 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.