Question

10 years ago the average age of all the 25 teachers
of the Girls college was 45 years. 4 years ago, the principal has
retired from her post at the age of 60 year. So after one year a new
principal whose age was 54 years recruited from outside. The present
average age of all the teachers is, if principal is also considered as a
teacher:
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Answer 1

Answer:

54.6 years

Step-by-step explanation:

Let the sum of ages of 25 teachers before 10 years be "x".

X/25 = 45

x = 45*25

x = 1125

After 4 years a principal was recruited at the age

of 60 years.

So, 1125 + 24(4) - 60

= 1161

And also , after 1 year a new principal was

recruited at the age of 54.

Then we get,

1161+24(1) + 54

= 1239

After 5 years we get the present ages, hence we should add 5 years to each of the teachers,

i.e., 1239+25(5)

=1364

Average age of present ages of all the teachers

=1364/25

= 54.6 years.