According to Trail Count, the annual survey of San Jose's off-street bicycle and pedestrian trail users, approximately 24% use trails daily. Suppose 12% use trails daily for exercise, and 8% use trails daily for commuting. Suppose a trail user is randomly selected. (Round your answers to four decimal places.) (a) Given that the person uses trails daily, what is the probability that he/she uses the trails for exercise?

a) 0.5

Step-by-step explanation:

a)

Let T be the event that person uses trails daily and E be the event that person uses trails for exercise.

We have to find the probability that person uses the trails for exercise given that the person uses trails daily which can be denoted as P (E/T).

P (E/T) = P (E∩T) / P (T)

We are given that P (T) = 0.24 and P (E∩T) = 0.12. So,

P (E/T) = 0.12/0.24

P (E/T) = 0.5

Thus, the probability that person uses the trails for exercise given that the person uses trails daily is 50%