Find the mode of the following data in each case : 7, 9, 12, 13, 7, 12, 15, 7, 12, 7, 25, 18,7

Find the mode of the following data: 12, 14, 12, 16, 15, 13, 14, 18, 19, 12, 14, 15, 16, 15, 16, 16, 15,17, 13, 16, 16, 15, 15, 13, 15, 17, 15, 14, 15, 13, 15, 14

Find the median of the following data: 12,11,6,7,10,17,9,15,13

Find the mean and variance for the following data:- 6, 7, 10, 12, 13, 4, 8, 12

Find the mean deviation from the median for the following data : 3, 9, 5, 3, 12, 10, 18, 4, 7, 19, 21.

Find the sum of the following APs :- 2, 7, 12, ... to 10 terms.