Question

A group of people were asked if they had run a red light in the last year. 483 responded "yes", and 147 responded "no". Find the probability that if a person is chosen at random, they have run a red light in the last year.

Answer 1

Concept

The probability is the extent to which an event is likely to occur, measured by the ratio of the favorable cases to the whole number of cases possible.

Given:

483 responded yes

147 responded no

The total number of respondents are:

`\begin{gathered} =\text{ 483 + 147} \\ =\text{ 630} \end{gathered}`

The probability of an event e can be calculated using the formula:

`\text{Probability of an event =}\frac{Number\text{ of required outcomes}}{Total\text{ number of possible outcomes}}`

Required:

The probability that if a person is chosen at random, they have run a red light in the last year

Substituting we have:

`\begin{gathered} P\text{ =}\frac{Number\text{ of people that responded yes}}{Total\text{ number of respondents}} \\ =\text{ }(483)/(630) \\ \end{gathered}`