Question

A man has mislaid his wallet. He thinks there is a 0.4 chance that the wallet is somewhere in his bedroom, a 0.1 chance it is in the kitchen, a 0.2 chance it is in the bathroom, and a 0.15 chance it is in the living room. What is the probability that the wallet is a) somewhere else? b) in either the bedroom or the kitchen?

Answer 1

a. Probability = 0.15

b. Probability = 0.3

Explanation:

Given

`P(Bedroom) = 0.4`

`P(Kitchen) = 0.1`

`P(Bathroom) = 0.2`

`P(Living\ room) = 0.15`

Solving (a): Probability of being somewhere else

This is calculated by subtracting the sum of given probabilities from 1.

`Probability = 1 - (0.4 + 0.1 + 0.2 + 0.15)`

`Probability = 1 - 0.85`

`Probability = 0.15`

Solving (b): Probability of being in bedroom or kitchen

This is calculated as:

`Probability = P(Bedroom) + P(Kitchen)`

`Probability = 0.2 + 0.1`

`Probability = 0.3`