On combining two groups of students having 30 and 40 average marks respectively in an exam, the resultant group has an average score of 34. Find the ratio of the number of students in the first group to the number of students in the second group.

In Arun’s opinion his weight is greater than 65 kg but less than 72 kg. His brother does not agree with Arun and he thinks that Arun’s weight is greater than 60 kg but less than 70 kg. His mother’s view is that his weight cannot be greater than 68 kg. If all of them are correct in their estimation, what is the average of different probable weights of Arun?

The total of the ages of a class of 75 girls is 1050 years the average age of 25 of them is 12 years and that of another 25 is 16 years Find the average age of the remaining girls

Shashikala spends 14% of her monthly salary on clothes, 5% on pet care and 11% on rent. She spends half the remaining amount on travel and saves the remaining Rs. 10500. What is her monthly salary?

What is the difference between the mean and median of the following set of numbers?

S = {345, 980, 120, 670, 665, 700}