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GB-18-06-001 · Conditional probability

Of 57 students, 30 study art, 29 study music and 8 study both. A student who studies art is chosen at random. Find the probability that this student also studies music.

Venn Diagrams: Conditional Probability {B | A} Booklet p. 62
Method
P(B given A) = (Double shaded overlap A ∩ B) / (Total in A)
Worked Example (GB-18-06-001)
1)
ArtMusic228216
2)
Conditioning on art restricts the sample space to the 30 art students.
3)
P(music∣art)=830=415P(\text{music}\mid\text{art})=\frac{8}{30}=\frac{4}{15}
Ans = 415\frac{4}{15}