Question

The average age of 20 employees in a factory is 30 years. if the supervisors age is added the average age is increases by one. what is the age of the supervisor?

Answer 1

Average age =total age of employee /no. Of employee
30=total age of employee /20
600=total age of employee
adding the age of supervisor will make the average 31 therefore
31=new total age of employee /21
651=new total age of employee
age of supervisor is equal to 651-600
=51