Respuesta :

jerryguo2282769

Answer:

11 if the average was 4 years ago.

Explanation:

4 years ago would be the average from 4 years later the total age 4 years ago.

adbid

Answer:

the avg age = 15 years

total stds= 9 years

total age 4 yrs age = 15-4

=11

total age= sum of the age of all the students

=11×9(the total students)

=99

; the total age 4 years ago was 99...

i am a maths dropout... I might not be right :(