The Venn diagram below shows students that are studying a science subject. The Venn diagram shows those studying biology, chemistry, both or neither. What is the probability of a student studying biology, B, given the student is also studying chemistry, C?
To find the probability of a student studying biology, given that the student is also studying chemistry, we need to find the intersection of the "biology" circle and the "both" circle, and divide it by the total number of students studying chemistry.
From the Venn diagram, we see that the intersection of the "biology" circle and the "both" circle contains 20 students.
The total number of students studying chemistry is 60 (40 in the "both" circle and 20 in the "chemistry only" circle).
Therefore, the probability of a student studying biology, given that the student is also studying chemistry, is:
P(B|C) = 20/60 = 1/3 = 0.33
So, the probability of a student studying biology, given the student is also studying chemistry, is 0.33 or 33%.