Are two 8 GB DDR3 (1600) better than two 8 GB DDR3 (1600) + one 4 GB DDR3 (1333)? [closed]

I have an old computer setup which has two 8 GB DDR3 (1600) RAM. I have found another 4 GB DDR3 (1333) RAM and trying to understand whether adding this 4GB RAM with those already mounted 16GB RAM will increase the computer performance or not.

I don’t have much knowledge on computer hardware. If anybody could give me an answer in layman’s term, I would be grateful.