Answer: The answer is 96 wizards.
Step-by-step explanation:
So what I like to do is fraction formatting.
you start with x/blank and
you do cross multiply divide
and multiple 120 by 80(=9600) and divide by 100 (=96) because wizards are 20% less of the population than goblins, so they are equivalent to 80% of the goblins! Hope this helped!