Chance Rules pp 105-119

# Puzzling Probabilities

• Brian Everitt
Chapter

## Introduction

The previous chapter on conditional probability dealt with some serious issues. Chapter which deals with risk assessment, will also have a serious side. In this chapter, as a change of pace, we shall explore some more entertaining and often paradoxical probability problems.

## A New Neighbour

1. (1)

A new neighbour arrives at your door to borrow a cup of sugar. You ask whether she has any children. She replies that she has two. ‘Any boys’, you ask? ‘Yes’, she says, as she takes her sugar and leaves.

2. (2)

A new neighbour arrives at your door to borrow a cup of sugar. You ask whether she has any children. ‘Yes’, she replies, ‘one five years old and one who is nine’. ‘Is the older a boy’, you ask? ‘Yes’, she says, as she takes her sugar and leaves.

3. (3)

A new neighbour arrives at your door to borrow a cup of sugar. You ask whether she has any children. She replies that she has two. ‘Any boys’, you ask? ‘Yes’, she says, as she takes her sugar and leaves. Next day you see her...

## Keywords

Conditional Probability Death Penalty Racial Equality Walk Away August Temperature
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.