Answer: Sandra bikes 11 2/5 miles more than Pedro.
Step-by-step explanation:
Pedro biked from his house to the nature preserve , a distance of 23 4/5 miles. Converting 23 4/5 miles to improper fraction, it becomes 119/5 miles.
Sandra biked from her house to the lake, distance of 12 2/5 miles. Converting 12 2/5 miles to improper fraction, it becomes 62/5 miles.
Therefore, the difference in number of miles biked by Sandra and Pedro is
119/5 - 62/5 = 57/5 = 11 2/5 miles
