A batsman in his 20th innings make a score of 110 and there by increases his average by 4. What is his average after 20 innings? 

The average salary of all the staff in an office of a corporate house is Rs 5,000. The average salary of the officers is Rs 14,000 and that of the rest is Rs 4,000. If the total number of staff is 500, the number of officers is

A class has 90 students, of which 60 percent are girls and the rest are boys. Boys' average score in English is 30 percent higher than girls. If the average score of all students in English is 56, then what is the average score of only girls in English?

The average of nine numbers in M and the average of three of these is P. If the average of remaining numbers is N, then

The average of the marks obtained in an examination by 8 students was 51 and by 9 other students was 68. The average marks of all 17 students was: 

5 number whose average is 76, the first is 3/7 times the sum of other 4. the first number is: 

The average of 8 readings is 24.3, out of which the average of first two is 18.5 and that of next three is 21.2. If the sixth reading is 3 less than seventh and 8 less than eight, what is the sixth reading?