The answer to this question is 168 hours. Why? Well, like the problem said, we can use a proportion. Because Mario spends 8 hours each week practicing soccer, our unit rate is 8/1 (that simplifies to 8 because 8 divided by 1 is 8). Now that we have our unit rate, we can multiply this by 21/1 weeks to identify the total amount of hours Mario spends practicing soccer after 21 weeks. 8/1 x 21/1 can be simplified to 8 x 21. When calculating, the answer is 168. That is how many hours Mario will spend practicing soccer after 21 weeks.
Your final answer: A.