15 ounces, 1 bag of tortilla chips
5 servings in 1 bag
240 milligrams salt in 1 serving
Given information includes quantity of "salt", and question asks about "sodium". If literally what is written is what you are to use, you also need 22.9898 for atomic weight of sodium, and 58.44 formula weight for sodium chloride (common table salt, ignoring minor quantities of other materials).