In an excel sheet, there are 5 rows and 5 columns where you can put either 5 or 10 . Suppose the number of 5 s in \(x^{th}\) row of the table is \(x-1\) for each row. What is the arithmetic mean of all the numbers in the table?
Explanation: Number of 5 s in x th row is \(x-1\). So number of 5 s in 1 st row is 0 . Number of 5 s in 2 nd row is 1 . Number of 5 s in 3 rd row is 2 . Number of 5 s in 4 th row is 3 . Number of 5 s in 5 th row is 4 . In total there are \(5\times5 = 25\) cells. Among them, 10 are filled with \ 5 \". So
