f a person needs 2,000 calories per day yet regularly consumes 3,000 calories per day, what most likely will happen, according to the “calories in equal calories out” equation?

The person will probably become fat because they are consuming more calories than the body needs to function. Because they only need 2,000 calories, their body has no need for an extra 1,000 calories so the body will store it as fat to access later.