To find the decimal part of the minutes you will need the area of doughnut #246.
Assume the doughnut is flat, with an overall radius of 10, the radius of the hole is 5.
The area of a circle is πr²
For the North add 31 to the area and for West subtract 89 from the area.
Don't forget that doughnut #246 was made in Indiana in 1897
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