Conversions for Lat/Long

A) Converting Degrees and Minutes to Degree and Decimal (Decimal Degrees)

Question: How does one Convert a Degrees and Minutes Location to a Degree and Decimal (Decimal Degree) location?

First, remember that we are NOT talking about changing or converting the WHOLE degree part of a location. So in a reading of 43 51'(min), we are not going to do anything to the 43 part of this location. It is a whole degree so there is nothing to convert.

What we are talking about is the part of, or fraction of the location reading because that can be expressed in two ways:

a) in minutes (1/60 of a degree) ; or
b) in decimal percentages (1/100 of a degree)

Background on converting from minutes to decimal percentage.

1) Each whole degree is comprised of 60 minutes.

2) To convert a minute into decimal percentage just divide the MINUTE number by 60:

For instance:
6 minutes divided by 60 = 0.10 (or 10% of a degree)
30 minutes divided by 60 = 0.50 (or 50% of a degree)

HERE'S AN EXAMPLE:

 The conversion of 43 deg 51'(min), would be: 43 degrees stays the same; then 51 minutes is divided by 60 = 0.85 (or 85% of a degree). So the complete conversion to DECIMAL DEGREES is: 43.85 degrees.

Guidelines
Here are some guidelines for conversions to use as cross checks as you do conversions of minutes to decimal degrees:

 Minutes Decimal Degree Minutes Decimal Degree 1 .0166 31 2 32 3 .05 33 .55 4 34 5 35 6 .10 36 .60 7 37 8 38 9 .15 39 .65 10 .1666 40 11 41 12 .20 42 .70 13 43 14 44 15 .25 45 .75 16 46 17 47 18 .30 48 .80 19 49 20 50 21 .35 51 .85 22 52 23 53 24 .40 54 .90 25 55 26 56 27 .45 57 .95 28 58 29 59 30 .50 60 1.00 (a whole degree)

B) Converting Degree and Decimal (Decimal Degrees) to Degrees and Minutes:

Question: How does one Convert a Degree and Decimal (Decimal Degree) location to a Degrees and Minutes Location?

Basically, the calculation is the reverse of converting minutes to decimals. In short, rather than dividing the minutes by 60, you multiply the decimal degree by 60, and that gives you the conversion to MINUTES.

HERE'S AN EXAMPLE:

 The conversion of 43.85 degrees, would be: 43 degrees stays the same; then 0.85 deg is multiplied by 60 = 51 minutes. So the complete conversion to degrees and minutes is: 43 51' (MINUTES)

Guidelines
Again the basic rule is, multiply the decimal degree by 60.

Here are a few more guidelines for conversions to use as cross checks:
.15 of a degree multiplied by 60 = 9 minutes
.166 of a degree multiplied by 60 = ~ 10 minutes

or .50 of a degree multiplied by 60 = 30 minutes
.70 of a degree multiplied by 60 = 45 minutes
.95 of a degree multiplied by 60 = 57 minutes
1.00 of a degree multiplied by 60 = 60 minutes/1Whole Degree

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