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?

What is the average of all numbers between 100 and 200 which are divisible by 13?

The average age of five girls is 11. The oldest among them is 15 years old. What is the average age of the others?

12 kg of rice costing 30 per kg is mixed with 8 kg of rice costing 40 per kg. The average per kg price of mixed rice is

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

The average monthly expenditure of a family for the first four months is ₹ 2570, for the next three months ₹ 2490 and for the last five months ₹3030. If the family saves ₹ 5320 during the whole year, the average monthly income of the family during the year 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:

The mean weight of 34 students of a school is 42 kg. If the weight of the teacher be included, the mean rises by 400 grams. Find the weight of the teacher (in kg.)