Final answer:
Without additional information, we cannot determine the exact percentage of students age 15 and above who travel to school by bus.
Step-by-step explanation:
To find the percentage of students age 15 and above who travel to school by bus, we need to compare the number of students who travel by bus to the total number of students in that age group. However, we don't have that information in the given question.
We need more data to calculate the percentage. Without additional information, we cannot determine the exact percentage of students age 15 and above who travel to school by bus.