WPF: Setting the Width (and Height) as a Percentage Value

Question

Say I want a TextBlock to have its Width equal to it\'s Parent container\'s Width (ie, stretch from side to side) or a percentage of

Answer 1

For anybody who is getting an error like : '2*' string cannot be converted to Length.

    
        
        
    
    
        
    

    Your text block a:
    Your text block b: