The average age of the members of a club increases to 27 when 3 more persons whose average age is 29 join them from 26. What is the number of members in the club now?

I did not understand this question at all. I will be really greatful if I get an explanatory answer

Total 6 person before adding 3 more person. Solution: Total age of x person = 26x Add 3 person with avg age 29 i.e total age of x+3 person = 26x +29*3 Given after adding 3 person avg age is 27. Total age = 27*(x+3) Now solve the equation 26x+29*3=27*(x+3) Ans 6 Total person 6+3=9