ADDITIONAL PRACTICE QUESTIONS. CALCULATION OF INTRAVENOUS FLOW RATES. When answering the following questions, be sure to: â¢ For IV drip rates (gtt/ min) and flow rates (mL/ hr) round off to the nearest whole. number when applicable. â¢ state the unit of measurement in each answer. CONVERTING TO mL/ hr. Using this formula will help you to answer the following questions: