I FOUND YOUR COMPLETE QUESTION IN OTHER SOURCES.
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For this case, the first thing we are going to do is add the number of students in each of the disciplines.
We have then:
walk = 9
bike = 8
skateboard = 3
Total: 20
The percentage sought is then:
(3/20) * (100) = 15%
Answer:
percentage of the total students chose skateboarding is:
D.) none of these