Young mathematician

One young mathematician was bored again. He found that the average age of people in the room where the seminar is equal to its count. Then his 29-year-old brother entered this room. Even then, the average age of all present was the same as the count of people. How many people were in the room at the beginning?

Correct answer:

n =  14

Step-by-step explanation:

n+1=(n n+29)/(n+1) (n+1) (n+1)=(n n+29) 2n=28  n=28/2=14  t=(14 14+29)/15=15

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