The average score in Mathematics of 90 students of section A and B of class IX was 63. The number of students in A were 10 more than those in B. The average score of students in A was 30% more than that of students in B. The average score of students in B is:

The mean of 9 observations is 16. One more observation is included and the new mean becomes 17. The 10th observation is

The average of three numbers a, b and c is 2 more than c. The average of a and b is 48. If d is 10 less than c, then the average of c and d is:

If the average marks of three batches of 55, 60 and 45 students respectively is 50, 55 and 60, then the average marks of all the students is?

The average of 8 numbers is 27. If each of the numbers is multiplied by 8, find the average of new set of numbers.

A batsman scored 87 runs in the 21st match in his career. His average of runs per match increased by 2. What was his average before the 21st match?

The average age of six members of a family is 40 years. If the age of a guest is included, then the average age increases by 12.5%. What is the age (in years) of the guest?

What is the average of the first five prime numbers?