Puzzles

Forum Archive : Puzzles

 
Least shots on a blot within direct range

From:   Raymond Kershaw
Address:   rkershaw@hued.demon.co.uk
Date:   30 December 1998
Subject:   BACKGAMMON GALORE
Forum:   E-mail
Google:   bu3CADAhVii2gw4p@hued.demon.co.uk

I wonder if you would like to add the following to your puzzle section.
This was published as an article by me in the Summer 1982 Backgammon
Times.

With no men on the bar, what is the smallest number of shots out of 36
with which it is possible to hit a blot which is in range of a direct
shot ?

Numbering the points from X's perspective, X has one man on his 24pt and
two on each of his 22pt, 21pt, 7pt, 5pt, 4pt, 3pt and 2pt.  O has one
man on X's 19pt and one man on X's 1pt.

O on roll has a direct shot at X's blot on the 24pt.  But it can be hit
by only three shots - 55 and 41.  (Note that 56, 54, 53, 52 and 51 must
be played without hitting.)

Not only can O hit with 55 and 41 but indeed he must hit with these
three rolls.
--
raymond kershaw
 
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