It has been given that among 9 passengers, 5 can speak Kannada, 2 can speak both Kannada and English. The number of passengers who can speak only English is
A. 6
B. 5
C. 4
D. 3

Hint-By using the property of sets , remove the number of people who speak who speak both languages and people speaking languages other than English.

Given-The total number of passengers=9
 Number of passengers who can speak Kannada=5
No of passengers who can speak both Kannada and English=2
Let us consider the no of passengers speaking only English=x
So, the number of passengers speaking only English=Total no of passengers-(number of passengers who speak only Kannada +number of passengers who speak both English and Kannada)
So, x=9-(3+2)=4
So, we get the number of passengers who speak only English=4
So, option C is the correct answer to this question
Note: In this case, we have been asked to find out the people who speak only English, in case we have been asked to find out some other data, make use of the appropriate formula and solve it, we can also make use of the standard formula of sets and solve this type of questions