Which machine performs both input and output functions?

A fax machine is a device that performs both input and output operations, which is why it is considered a combination device in computing.

Here’s how it works:

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  As an input device, the fax machine scans a physical document and converts the contents into electronic signals for transmission.

  
  


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  As an output device, it receives the signals sent by another fax machine and prints out a physical copy of the received document.

  
  

This means it takes data in (input), processes it, and then gives out data (output), which clearly shows that a fax machine serves both purposes.