The problem statement for question 4 is incomplete as the number of students who like only English is missing. For the purpose of solving parts (a) and (b), we will assume that 60 students like only E

Here's the solution to question 4:

The problem statement for question 4 is incomplete as the number of students who like only English is missing. For the purpose of solving parts (a) and (b), we will assume that 60 students like only English, i.e., $n(E \text{ only}) = 60$.

Given:
Total number of students, $n(U) = 180$
Number of students who like only Nepali, $n(N \text{ only}) = 45$
Number of students who like neither English nor Nepali, $n(E \cup N)' = 15$
Assumption: Number of students who like only English, $n(E \text{ only