Past exam of the mathematics course of the year 1 of the natural sciences course of the University of Cambridge / 2019 / Paper 2 / 6 / b

Table of contents
- Solution b

Solution

Write

U = A \cup B \cup C

. Since

D \subseteq U

, their intersection is

U \cap D = D

. Therefore the definition of conditional probability gives

P (U ∣ D) = \frac{P ( U \cap D )}{P ( D )} = 1, P (D) > 0.

The positive-probability condition is necessary: if

P (D) = 0

, this elementary definition of conditional probability does not assign a value.

 Ancestors (12)

 View article source

 Discussion (0)

There are no discussions about this article yet.

 Articles by others on the same topic (0)

There are currently no matching articles.

  See all articles in the same topic Create my own version