$0.13 per ounce. 5 pounds of birdseed cost $10.40, then the price per ounce is $0.13.
The easiest way to solve this problem is using arithmetic operations and unit conversion.
We have to calculate the price per pound. Let's divide $10.40 by 5 pounds.
10.40/5 = 2.08
The price per pound is $2.08
To calculate the price per ounce, with 1 pound = 16 ounces. Let's divide $2.08 by 16 ounces.
2.08/16 = 0.13
The price per ounce is $0.13