In a school with 600 students the average age of the boys is 12 years and that of the girl is 11 years. If he average age of the students is 11 years 9 months, then the number of girls in the school is

Find the average of the following sets of numbers.

693, 456, 876, 532, 934, 691, 596, 398, 682

Average of 11 number is 30. If the average of first 10 numbers is 22, then find the 11th number?

What will be the average of the following set of scores?
59, 84, 44, 98, 30, 40, 58

Find the average of the following set of numbers 148, 88, 184, 166, 96, 122

In the afternoon, a student read 100 pages at the rate of 60 pages per hour. In the evening, when she was tired, she read 100 more pages at the rate of 40 pages per hour. What was her average rate of reading the pages per hour?