Answer:
You could compare the ounces or weight, the price per unit, or overall quality.
Explanation:
You could use the ounce/weight to check which weighs more, or has more in it. Then figure out which is more reasonable. You could use the price per unit, and the ounce/weight because the price per unit/ price per ounce could be more expensive, or less expensive and make more sense to buy. Or you could just use overall quality. You can have an item with more in it, but have lower quality contents, when you could have a smaller amount with better quality contents, which might cost a little more.\
-Hope this helped