The average of five numbers is 7. If three new numbers would be added, then the new average comes out to be 8.5. What is…

The average age of 30 students in a class is 15 years. If 6 students of this class have the average age of 16 years, the…

Average of a, b, and c is 11; average of c, d and e is 17; average of e and f is 22 and average of e and c is 17. Find o…

The average of 10 items was found to be 80 but while calculating, one of the items was counted as 60 instead of 50. Then…

The average weight of 3 men, A, B and C is 84 kg. Another man D joins the group and the average now becomes 80 kg. If an…

If the average of x and $$\frac{1}{x}$$ (x $$ \ne $$ 0) is M, then the average of x<sup>2</sup> and $$\frac…

Ten years ago, the ages of the members of a joint family of eight people added up to 231 years. Three years later, one m…

A library has an average of 510 visitors on Sundays and 240 on other days. The average number of visitors per day in a m…