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.) 

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

The average score of top 6 batsmen of Indian cricket team in a match is 46. If the 7th batsman is included, the average becomes 50. If the 8 batsman comes and scores 34 runs, then find the ratio of the average scores of top 6 and top 8 batsmen.

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:

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?

A man purchased 7 bags of rice at the rate of  ₹ 800 each, 8 bags of rice at ₹ 1000  each and 5 bags of rice at the rate of  ₹ 1200 each. What is the average cost of one bag of rice?

The average of six numbers is 3.52. The average of two of them is 3.7, while the average of other two is 2.5. What is the average of the remaining two?

The average monthly savings of Shifa for the first 5 months is Rs. 2120, for the next 3 months is Rs. 4260 and for the remaining months of the year is Rs. 3140. Now, the average monthly expenditure for the complete year is Rs. 11000. Find the total income of the year