Question

the average age of 10 students in a class is 13years and the average age of the remaining 15 students is 11 years 4 months. what is the average age of a student in that class?

Answer 1

Average 10 students age = 13 years
Therefore 10 students age = 130 years
Average 15 students age = 11 years 4 months = 11.3 yrs
Therefore 15 students age = 169.5 years

Total students in class = 10 + 15 = 25
Total age of students in class = 130 + 169.5 = 299.5 years
Therefore average age of a student = $\frac{299.5}{25}$ = 11.98 years
On simplifying 11.98 yrs = 11 years 11 months 22 days 19 hours 12 minute :D