In a group of 80 people, 35 speak only Hindi and 20 speak only English. If everyone speaks at least one language, how many speak both?
Answer: C
The total number of people is the sum of those who speak only Hindi, only English, and both.
Total = (Only Hindi) + (Only English) + (Both)
80 = 35 + 20 + (Both)
80 = 55 + (Both)
Both = 80 - 55 = 25.