Answer:
29 pounds of type A coffee was used
Step-by-step explanation:
David's shop makes a blend that is a mixture of 2 coffee
Type A costs $4.10
Type B costs $5.25
Let a represent the number of pounds of type A coffee used
Since this month's blend used twice as many pound of type B coffee as type A
a + 2a
The total cost is $423.40
Therefore the amount of pounds of type A coffee used can be calculated as follows
4.10a + 5.25(2a)= 423.40
4.10a + 10.5a= 423.40
14.6a= 423.40
a= 423.40/14.6
a= 29
Hence 29 pounds of type A coffee was used