Road Sign Math

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Black Dog

June 5th, 2005 · 5 Comments

Minnesota

Long before the game of finding mathematically significant road signs, this sign used to always catch my eye. Black Dog Road. It sounds like a place where some mystery happened years ago. If you were sitting around a campfire with your grandpa you could easily envision him whipping out a story about the Ghost on Black Dog Road. This entire scene is filled with stories waiting to happen. Burnsville itself brings overtones of fire. Add to that Cliff Road and you’ve got the ingredients for a great ghost story. Maybe even a ghostly poem of terror.

The math here is a little elusive. We can remove the A and B from 4A and 4B and just use them as fours. Your eye can get distracted with the 2nd 4B and 15 MPH signs, however, they are independent signs and do not invalidate our main sign. After clearing these unrelated signs and leaving the stories of mysterious black dogs behind, the math becomes clear.

( 4 \times 4 ) -1 = 15

This sign was found on 35W Southbound heading towards Burnsville, in Minnesota. The GPS coordinates are N44 47 52.8 W93 17 22.4. See sign on map!

Tags: Minnesota

5 responses so far ↓

  • 1 Alyosha // Jun 24, 2005 at 2:03 pm

    But I see more numbers in this image, which you have left out, so: 15*(1^(4×4/4))=15.

  • 2 Alyosha // Jun 24, 2005 at 2:04 pm

    In fact there are more numbers still. My mistake.

    15*(1^(4+4^4/60200))=15

  • 3 Road Sign Math // Jun 26, 2005 at 4:27 pm

    Alyosha,

    Thanks for posting the additional formulas, however, they are not required. If you examine the picture closely you will find that the numbers you are referencing are not attached to the same gantry as the numbers that are included in the original posting. As a result, there use is not required, in fact, they cannot be used.

  • 4 Sue // Jul 1, 2005 at 1:09 pm

    I, too, wondered about the origin of the name of this road… same thinking in that a vicious black dog guarded the road :)

  • 5 Scott // Aug 23, 2005 at 3:07 am

    Black Dog is the power plant that is about a mile or two east of these signs.

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