% 
% Written by:
% -- 
% John L. Weatherwax                2007-09-10
% 
% email: wax@alum.mit.edu
% 
% Please send comments and especially bug reports to the
% above email address.
% 
%-----

clc; 

lambda = 18;
mu     = 10; 
s      = 2; 

rho    = lambda/(s*mu); 
alpha  = lambda/mu; 

%pt a:
p0 = (1-rho)/(1+rho); 
fprintf( 'p_0 = %10.6f\n', p0 );
% pt b:
C = (alpha^2) / (2+alpha); 
fprintf( 'C = %10.6f\n', C );
% pt c:
dWQ = 1/(s*mu-lambda); 
fprintf( '$W_Q = %10.6f (hour) = %10.6f (min)\n', dWQ, dWQ*60 );
% pt d:
W_Q = (1/mu)*( alpha^2 / ((2-alpha)*(2+alpha)) ); 
fprintf( 'W_Q = %10.6f (hour) = %10.6f (min)\n', W_Q, W_Q*60 );
% pt e:
L_Q = W_Q * lambda; 
fprintf( 'L_Q = %10.6f\n', L_Q );
% pt f: 
W = (1/mu) + W_Q; 
fprintf( 'W = %10.6f (hour) = %10.6f (min)\n', W, W*60 );
% pt g: 
L = W*lambda; 
fprintf( 'L = %10.6f\n', L );
% pt h:
P = C*exp( -(s*mu-lambda) );
fprintf( 'P(E) = %10.6f\n', P );