Calculate the correct value:
 
An object 3 \(cm\) high is placed at a distance of 20 \(cm\) from a concave mirror which produces a real image \(3\) \(cm\) high. Find the position of the image.
  
The position of the image is  \(cm\) in front of the concave mirror.
 
[Note: Enter your answer with no decimal digits.]