Information about **Experimental Probability** can be captured in a number of different ways. If there is only one piece of information being captured, such as the roll of a dice, or the colour of cars on a motorway, then the information can be captured in a **One-Way table**.

One-way tables can be shown either vertically or horizontally.

One-way tables do not always show a total, although a total is required to work out the probability of an event happening.

A die was rolled twenty times. The results were plotted onto a one-way table:

Throw | 1 | 2 | 3 | 4 | 5 | 6 |

Frequency | 3 | 4 | 4 | 2 | 3 | 4 |

Which value appeared the least often?

There were only 2 instances with a value of 4; the other values appeared more often.

Answer: 4

A survey of cars along a road was recorded in a notebook. The entry for the number of Red cars was obliterated by rain. If it was known that `frac(1)(4)` of the cars were white, and that an `frac(1)(8)` of the cars were red.

How many red cars were there?

White | Red | Blue | Green | Black | Silver |

8 | ? | 7 | 5 | 3 | 5 |

There were only half as many red cars as white cars; therefore there were 4 red cars.

Answer: 4

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