Final answer:
Assuming each worker has the same production rate, 15 workers would produce approximately 225 pens weekly. None of the answer choices provided match this calculation, indicating a possible error in the question.
Step-by-step explanation:
To determine the weekly production rate of pens, given that each worker produces the same output, we first look at the production of books. With 35 workers, the factory produces 500 books a week. This means each worker produces ≈15 books a week (≈ means 'approximately equal to'). Now, if there are 15 workers assigned to produce pens, we multiply the number of workers by the production rate per worker. Therefore, 15 workers each producing approximately 15 items a week would result in a total production of 225 pens per week.
However, none of the provided options exactly matches '225 pens' per week. Given the closest options available, the likely assumption is that there was an error within the question as the exact answer does not align with any of the options (A) 300 pens, (B) 500 pens, (C) 700 pens, or (D) 800 pens. Therefore, based on the given information and assuming each worker has the same production rate, the answer would have been '225 pens' rather than any of the options provided.