Because the words we use are derived from a time when people used base twelve rather than base ten. Also the reason for "dozen" & "gross".
It goes back about 500 years or so.
It is a hendecahedron.
Hendecagon is 11. Dodecagon is 12.
It is 11,12,111
Eleven and eleven thousandths.
eleven thousand eleven hundred and eleven rupees is written as : Rs. 11,111.
Eleven identical children are called undecaplets.
An eleven sided shape is called a hendecagon.
They are called hendecagons.
It is called a hendecagon or, less often, an endecagon.
Finger Eleven has 5 albums, they have one called Tip, one called Finger Eleven, one called The Greyest of Blue Skies, one called Them Vs You Vs Me, and one called life Turns Electic
a shape with eleven sides is called a undecagon
hendecagon
hendecagon
There were eleven
It is called a hendecagon.
Edward hopper
It is called a hendecagon, undecagon