First you have to find how many pounds she ate each month.
1 year=12 months
So you have to divide 320 by 12.
320÷12=26.6667
NOTE: Do not round yet because it can throw off your answer.
Now you need to convert that to ounces
1 pound = 16 ounces
Now you have to multiply 26.6667 by 16:
26.6667×16=426.6667
Now you round and get the answer of: 426.7