SOLUTION: Tulips, tulips, everywhere! There are tulips of every color and size - all arranged on floats for the first Tulip Bowl Parade. There are nine marshals stationed every two blocks al

Suppose the marshals are numbered 1 to 9 and stand like this:

Marshals   1   2   3   4   5   6   7   8   9   
Blocks     | | | | | | | | | | | | | | | | |

Whatever the answer is, it has to be the same answer as
as if the marshals were arranged this way instead:

Marshals   9   8   7   6   5   4   3   2   1
Blocks     | | | | | | | | | | | | | | | | |

There is only one way both arrangements could have the 
same answer, and that is if they all walked to where the 
middle marshal 5 is standing. So everybody except marshal 5
walks to where marshal 5 is standing, and marshall 5 just 
stays where he is.

So: 
marshals 9 and 1 each walk 8 blocks to where marshal 5 is standing.
That's 16 blocks for those two marshals. 
marshals 8 and 2 each walk 6 blocks to where marshal 5 is standing.
That's 12 blocks for those two marshals.   
marshals 7 and 3 each walk 4 blocks to where marshal 5 is standing.
That's 8 blocks for those two marshals.
marshals 6 and 4 each walk 2 blocks to where marshal 5 is standing.
That's 4 blocks for those two marshals.
marshal 5 walks 0 blocks, that is, he stays where he is.
That's 0 blocks for that marshal.

16+12+8+4+0 = 40 blocks total.

Edwin