Can anyone help me with this word problem?

Question

15 pounds of mixed birdseed sells for $8.85 per pound. The mixture is obtained from two kinds of birdseed, with one variety priced at $7.05 per pound and the other at $9.30 per pound. how many pounds of each variety of birdseed are used in the mixture?

Answer 1

let x be weight of birdseed that cost $7.05

let y be weight of birdseed that cost $9.30

 

so,

 

x + y + = 15

 

7.05x + 9.3y = 132.75

 

x = 15 - y

 

7.05(15 - y) + 9.3y = 132.75

 

105.75 - 7.05y + 9.3y = 132.75

 

2.25y = 132.75 - 105.75

 

2.25y = 27

 

y = 12 lbs.

x = 3 lbs.