Question

In a class of 100 students, 55 students have passed in physics and 67 students have passed in Mathematics. Find the number of students passed in Physics only.

Answer 1

Step-by-step by steo

Total number of students = n(P∪M)=100

Number of students who passed in physics= n(P)=55

Number of students who passed in maths= n(M)=67

Number of students who passed both physics and maths=n(P∩M)

⇒n(P∪M)=n(P)+n(M)−n(P∩M)

⇒100=55+67−n(P∩M)

⇒n(P∩M)=122−100

⇒n(P∩M)=22

Step - 2 : Find number of students who passed only in physics

Number of students passed in physics = 55

Number of students passed in physics and maths both = 22

∴Number of students passed only in physics = 55−22=33