Answer:Here's how to solve the problem: 1. Convert the mixed numbers to fractions:2¾ miles = 11/4 miles1⅛ miles = 9/8 miles 2. Find a common denominator for the fractions:The least common denominator for 4 and 8 is 8.11/4 miles = 22/8 miles 3. Add the fractions:22/8 miles + 9/8 miles = 31/8 miles 4. Convert the answer back to a mixed number:31/8 miles = 3 7/8 miles Answer: Olivia walked a total of 3 7/8 miles.