A survey of 300 parks showed the following. 15 had only camping. 20 had only hiking trails. 35 had only picnicking. 185 had camping. 140 had camping and hiking trails. 125 had camping and picnicking. 210 had hiking trails. Determine the number of parks that:

a. Had at least one of these features.
b. Had all three features.
c. Did not have any of these features.
d. Had exactly two of these features.

Step-by-step explanation:

This will be solved using set notation according to the venn diagram attached.

Let n(U) be the total number of parks surveyed

n(C) be those that had camping = 185

n(H) be those that had hiking trails = 210

n(C∩H) be those that had camping and hiking trails = 140

n(C∩P) be those that had camping and picnicking = 125

n(C∩P'∩H') be those that had only camping = 15

n(C'∩P'∩H) be those that had only hiking trails = 20

n(C'∩P∩H') be those that had only picnicking = 35

Find the calculation in the attached file

the answer is 8/21

hope this