Answer:
Noah needs 8 pounds of the coffee that costs $9.20 per pound and 12 pounds of the coffee that costs $5.50 per pounds
Step-by-step explanation:
Let the number of pounds of the coffee that sells for 9.20 be x while the number of pounds of the coffee that sells for 5.5 be y.
From the question, we know he wants to make 20 pounds of coffee
Thus;
x + y = 20 •••••••••••(i)
Let’s now work with the values
For the $9.20 per pound coffee, the cost out of the total will be 9.20 * x = $9.20x
For the $5.5 per pound coffee, the cost out of the total be 5.5 * y = $5.5y
The total cost is 20 pounds at $6.98 per pound: that would be 20 * 6.98 = $139.6
Thus by adding the two costs together we have a total of $139.6
So we have our second equation;
9.2x + 5.5y = 139.6 •••••••(ii)
From i, y = 20 - x
Let’s substitute this in ii
9.2x + 5.5(20-x) = 139.6
9.2x + 110 -5.5x = 139.6
9.2x -5.5x = 139.6-110
3.7x = 29.6
x = 29.6/3.7
x = 8 pounds
Recall;
y = 20 - x
y = 20-8
y = 12 pounds
