How many minutes in 21.5 hours?

Conversion formula

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

1 hr = 60 min

To convert 21.5 hours into minutes we have to multiply 21.5 by the conversion factor in order to get the time amount from hours to minutes. We can also form a simple proportion to calculate the result:

1 hr → 60 min

21.5 hr → T_(min)

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

T_(min) = 21.5 hr × 60 min

T_(min) = 1290 min

The final result is:

21.5 hr → 1290 min

We conclude that 21.5 hours is equivalent to 1290 minutes:

21.5 hours = 1290 minutes

Alternative conversion

We can also convert by utilizing the inverse value of the conversion factor. In this case 1 minute is equal to 0.00077519379844961 × 21.5 hours.

Another way is saying that 21.5 hours is equal to 1 ÷ 0.00077519379844961 minutes.

Approximate result

For practical purposes we can round our final result to an approximate numerical value. We can say that twenty-one point five hours is approximately one thousand two hundred ninety minutes:

21.5 hr ≅ 1290 min

An alternative is also that one minute is approximately zero point zero zero one times twenty-one point five hours.

Conversion table

hours to minutes chart

For quick reference purposes, below is the conversion table you can use to convert from hours to minutes

hours (hr)	minutes (min)
22.5 hours	1350 minutes
23.5 hours	1410 minutes
24.5 hours	1470 minutes
25.5 hours	1530 minutes
26.5 hours	1590 minutes
27.5 hours	1650 minutes
28.5 hours	1710 minutes
29.5 hours	1770 minutes
30.5 hours	1830 minutes
31.5 hours	1890 minutes

Conversion units

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

Hour

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.

Source: Wikipedia Topic: hour

Minute

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.

Source: Wikipedia Topic: minute