"Out of 10 teachers of a school, one teacher retires and in place of him a new teache
Channel: Doubtnut
Date: 2020-04-05

"Out of 10
 teachers of a school, one teacher retires and in place of him a new teacher
 25 years old joins. As a result of it average age of the teachers reduces by
 3 years. Age of the retired teacher (in years) is:
(a) 55 (b) 60 (c) 58 (d) 56"