The total ages in a class of 80 girls is 1070 year. The average age of 25 of them is 13 year and that of another 25 is 16 year. Find the average age of the remaining girls?
Answer & ExplanationOption: [A]
The total age of first 25 girls is 25 x 13 = 325 year
The total age of second 25 girls is 25 x 16 = 400 year
The total age of first 50 girls = 725 year
The number of girls remained to calculate 30
So the total age of these 30 girls is (1070-725) year = 270 year
270/30 = 9 year