Answer:
30 people.
Explanation:
In a survey it is found that 20% of the people preferred umpt juice to all other juices. 
Now, if 6 of the surveyed people are being preferred umpt juice, then we have to find the total number of people that were surveyed altogether.
So, 20% of the people being surveyed is equal to 6 people.
Therefore, 100% of the people is equal to 
 people. (Answer)
 people. (Answer)