## Result

309 hours equals 18540 minutes

## Converter

## Conversion formula

Multiply the amount of hours by the conversion factor to get the result in minutes:

309 hr × 60 = 18540 min

## How to convert 309 hours to minutes?

The conversion factor from hours to minutes is 60, which means that 1 hours is equal to 60 minutes:

1 hr = 60 min

To convert 309 hours into minutes we have to multiply 309 by the conversion factor in order to get the amount from hours to minutes. We can also form a proportion to calculate the result:

1 hr → 60 min

309 hr → T_{(min)}

Solve the above proportion to obtain the time *T* in minutes:

T_{(min)} = 309 hr × 60 min

T_{(min)} = 18540 min

The final result is:

309 hr → 18540 min

We conclude that **309 hours is equivalent to 18540 minutes**:

309 hours = 18540 minutes

## Result approximation

For practical purposes we can round our final result to an approximate numerical value. In this case **three hundred nine hours is approximately eighteen thousand five hundred forty minutes**:

309 hours ≅ 18540 minutes

## Conversion table

For quick reference purposes, below is the hours to minutes conversion table:

hours (hr) | minutes (min) |
---|---|

310 hours | 18600 minutes |

311 hours | 18660 minutes |

312 hours | 18720 minutes |

313 hours | 18780 minutes |

314 hours | 18840 minutes |

315 hours | 18900 minutes |

316 hours | 18960 minutes |

317 hours | 19020 minutes |

318 hours | 19080 minutes |

319 hours | 19140 minutes |

## Units definitions

The units involved in this conversion are hours and minutes. This is how they are defined:

### Hours

An hour (symbol: h; also abbreviated hr.) is a unit of time conventionally reckoned as 1⁄24 of a day and scientifically reckoned as 3,599–3,601 seconds, depending on conditions. The seasonal, temporal, or unequal hour was established in the ancient Near East as 1⁄12 of the night or daytime. Such hours varied by season, latitude, and weather. It was subsequently divided into 60 minutes, each of 60 seconds. Its East Asian equivalent was the shi, which was 1⁄12 of the apparent solar day; a similar system was eventually developed in Europe which measured its equal or equinoctial hour as 1⁄24 of such days measured from noon to noon. The minor variations of this unit were eventually smoothed by making it 1⁄24 of the mean solar day, based on the measure of the sun's transit along the celestial equator rather than along the ecliptic. This was finally abandoned due to the minor slowing caused by the Earth's tidal deceleration by the Moon. In the modern metric system, hours are an accepted unit of time equal to 3,600 seconds but an hour of Coordinated Universal Time (UTC) may incorporate a positive or negative leap second, making it last 3,599 or 3,601 seconds, in order to keep it within 0.9 seconds of universal time, which is based on measurements of the mean solar day at 0° longitude.

### Minutes

The minute is a unit of time or of angle. As a unit of time, the minute (symbol: min) is equal to 1⁄60 (the first sexagesimal fraction) of an hour, or 60 seconds. In the UTC time standard, a minute on rare occasions has 61 seconds, a consequence of leap seconds (there is a provision to insert a negative leap second, which would result in a 59-second minute, but this has never happened in more than 40 years under this system). As a unit of angle, the minute of arc is equal to 1⁄60 of a degree, or 60 seconds (of arc). Although not an SI unit for either time or angle, the minute is accepted for use with SI units for both. The SI symbols for minute or minutes are min for time measurement, and the prime symbol after a number, e.g. 5′, for angle measurement. The prime is also sometimes used informally to denote minutes of time. In contrast to the hour, the minute (and the second) does not have a clear historical background. What is traceable only is that it started being recorded in the Middle Ages due to the ability of construction of "precision" timepieces (mechanical and water clocks). However, no consistent records of the origin for the division as 1⁄60 part of the hour (and the second 1⁄60 of the minute) have ever been found, despite many speculations.