The mean of 23 observations is 36. If the mean of the first 12 observations is 32 and that of the last 12 observations is 39, find the 12th observation.

The average weight of Shivam, Rupesh and Mandar is 45 kg. If the average weight of Shivam and Rupesh is 38 kg and the average weight of Rupesh and Mandar is 50 kg, then find Rupesh's weight (in kg).

In a class, the number of boys is 40% more than that of girls. In an examination, the average marks obtained by boys is 20% less than the average marks obtained by girls. If the average marks obtained by all the boys and girls is 53, then what is the average marks obtained by the boys ?

The average weight of the girls in a group is 58 kg. When 5 girls of average weight 60 kg leave the group or 5 girls of average weight 55.5 kg join the group, the average weight of girls in both cases is equal. What is the number of girls, initially, in the group?

The average of first 148 odd natural numbers, is:

The weight of five tables in a shop are 9.8 kg, 12.42 kg, 25.38 kg, 4.426 kg and 32.388 kg. Shop keeper got one more table and now total weight is 100 kg. The weight of new table is

The average weight of Mohammad, Ashish and Kiran is 46 kg. Average of Mohammad and Ashish is 40 kg and that of Ashish and Kiran is 42 kg. What is the weight of Ashish(in Kg).

In a class, the average score of boys is 75 with 20 boys and the average score of girls is 85 with 30 girls. What is the overall average score of the class?

If the average marks of three sections of Class IX, having 30, 45 and 50 students, respectively, is 80, 75 and 90, then the average marks of all the students of Class IX, is:

The average weight of Akshay, Atul and Baban is 46 kg. If the average weight of Akshay and Atul be 39 kg and that of Atul and Baban be 46 kg, then the weight of Atul (in kg) is:

12 chairs and 6 tables were bought for Rs. 12,600. If the average cost of a table is Rs. 1,500, then find the average cost of a chair.