There are three categories of jobs HR, CA and PA. The average salary of the student who got the job of HR and CA category is 20 lakhs per annum. The average salary of student who got the job of CA and PA category is 40 lakhs per annum and the average salary of those students who got the job of CA and PA category is 30 lakhs per annum. What is the average salary of all three categories of jobs?(in lakhs per annum)

Let the salary of students who got the jobs of HR, CA and PA categories are A, B and C respectively.  The average salary the student who got the job of HR and CA category = 20 lakh per annum i.e. (A+B)/2 = 20 lakh per annum therefore, A + B = 20  ×  2 = 40 lakh per annum……..(i) the average salary the student who got the job of CA and PA category = 40 lakh per annum i.e. (B+C)/2 = 40 lakh per annum therefore, B + C = 40  ×  2 = 80 lakh per annum………(ii) the average salary the student who got the job of PA and HR category = 30 lakh per annum i.e. (C+A)/2 = 30 lakh per annum therefore, C+ A = 30  ×  2 = 60 lakh per annum…………(iii) Adding (i), (ii) and (iii) 2(A+B+C) = 40 + 80 + 60 2(A+B+C) = 180 lakh per annum A+B+C = 90 lakh per annum Which means total salary of HR, CA and PA is equal to 90 lakh per annum Average salary of HR, CA and PA = (A+B+C)/3 = 90/3 = 30 lakh per annum