function [] = chap_1_st_13
% 
% Written by:
% -- 
% John L. Weatherwax                2007-07-01
% 
% email: wax@alum.mit.edu
% 
% Please send comments and especially bug reports to the
% above email address.
% 
%-----

% the number of each individual possible sales:
%
nD = nchoosek(8,4)
nG = nchoosek(9,4) 
nP = nchoosek(10,4) 

% the total number of sales: 
%
nTotal = nD*nG*nP