Dynamically Load xaml in Silverlight

 This is sateesh, I am facing a problem in silverlight if you feel free please help because I suffered a lot for this.  The problem is
 
I have two xaml files Ex:- page1.xaml and page2.xaml
these two i am using in default.aspx page
 
in page1.xaml have two check boxes i.e. Add and Subtract
in page2.xaml have two textboxes and one textblock
 
when I am giving values in page2.xaml textboxes suppose textbox1.text =10 and text2.text=15
and when I click Add check box in page1.xaml i should show 25 in textblock.text in page2.xaml
 
this is my requirement I tried a lot but not got any solution please resolve this is issue
 
Thanks & Regards
Sateesh G