Find the average of all prime numbers between 30 and 50.

The average of marks scored by the students of a class is 68. The average of marks of the girls in the class is 80 and that of the boys is 60. What is the percentage of boys in the class? 

The average weight of 15 oarsmen in a boat is increased by 1.6 kg when one of the crews, whose weighs 42 kg is replaced by a new man. Find the weight of the new man (in kg). 

The average of 20 numbers is 32. If two numbers are 29 and 31, then what is the average of the remaining numbers (correct up to two decimals)? 

A team of 8 persons joins in a shooting competition. The best marksman scored 85 points. If he had scored 92 points, the average score for the team would have been 84. The number of points the team scored was

The average salary, per head, of all the workers of an institution, is Rs. 60. The average salary of 12 officers is Rs. 400; the average salary, per head, of the rest is Rs. 56. The total number of workers in the in situation is 

The average score obtained by Sandeep in 12 Tests is 25. Rumella has an average of 23 marks so far, but has competed in only 8 Tests. What average will Rumela have to earn in the remaining 4 Tests to be equal to Raghuveer's average?