The arithmetic mean of the scores of a group of students in a test was 52. The brightest 20% of them secured a mean scor…

The average age of Ram and his two children is 17 years and the average age of Ram's wife and the same children is 16 ye…

A student was asked to find the arithmetic mean of the numbers 3, 11, 7, 9, 15, 13, 8, 19, 17, 21, 14 and x. He found me…

The mean high temperature of the first four days of a week is 25°C whereas the mean of the last four days is 25.5&de…

The average weight of 15 students in a class increases by 1.5 kg when one of the students weighing 40 kg is replaced by …

A batsman makes a score of 84 runs in the 21<sup>st</sup> inning and thus increases his average by 2 runs. H…

The average of 11 results is 50. If the average of the first six results is 49 and that of the last six is 52, the sixth…

Out of four numbers the average of the first three is 16 and that of the last three is 15. If the last number is 20, tha…