plotting 100 times in same plot

I want to plot the output x1, for 100 times on same graph. Since i am introducing randn noise in signal, output must be changing little bit everytime. Therefore, i can figure out, effect of noise on the signal. Thanks in advance.

t  = [ 0 : 1 : 40 ]; % time samples 
  f  = 500;  % input frequency                    
  fs = 8000; % sampling frequency  
  x = sin(2*pi*f/fs*t);     
  init_phase = randn(1,length(t));
  x1 = x + init_phase;
  plot(x1);

Answer 1

[bio lim]

 t  = [0 : 40]; % time samples 
 f  = 500;  % input frequency                    
 fs = 8000; % sampling frequency  
 x = sin(2*pi*f/fs*t);

 for k = 1 : 100

 init_phase(k, :) = randn(1,length(t));
 x1(k,:) = x + init_phase(k,:)  

 end

 plot(x1);

Answer 2

[Mayank Lakhani]

Thanks coffee :). This will help me.