Hello! So Carlos' sister reads an average of 24 pages in 1 hour. He reads 144 pages in 3 hours. To find the unit rate Carlos reads, let's do some division. 144/3 is 48. Carlos reads an average of 48 pages in 1 hour. If you use mental math, 48 is double the amount of 24. 200% is just simply 2. 24 * 2 is 48. D is the only one that shows an answer that even fits for this scenario. Carlos' average reading rate is 200% of his sister's. The answer is D: 200%.
