The number on the right is how much the item is worth. If you are in Stack mode, the number on the left is how many of those items you have and the number on the right is how much those items all combined are worth.
The number on the right is how much the item is worth. If you are in Stack mode, the number on the left is how many of those items you have and the number on the right is how much those items all combined are worth.