Number of students in 30 class rooms in a school are given below. Construct a frequency distribution table for the data with a exclusive class interval of 4 (students).
`{:(25,30,24,18,21,24,32,34,22,20,22),(32,40,28,30,22,26,31,34,15,38,28),(20,16,15,20,24,30,25,18, , ,):}`

Construct a frequency distribution for the following series of numbers. 1,1,12,12,13,15,15,15,16,17,18,18,18,18,18,18,21,23,23,24,25,26,26

Construct a frequency distribution for the following series of numbers.2, 3, 4, 6, 7, 8, 9, 9, 11, 12, 12, 13, 13, 13, 14, 14, 14, 15, 16, 17, 18, 18, 19, 20, 20, 21, 22, 24, 24, 25.

Find the median of 9 observations 22, 32, 30, 18, 75, 62, 36, 12, 20.

If the median of 60 observations , given below is 28.5 , find the values of x and y . {:("Class interval","Frequency"),(0-10,5),(10-20,x),(20-30,20),(30-40,15),(40-50,y),(50-60,5):}

The following distribution gives the state-wise , teacher -student ratio in higher secondary schools of India . Find the mode and mean of this data . Interpret the two measures . {:("Number of students","Number of states"),(15-20,3),(20-25,8),(25-30,9),(30-35,10),(35-40,3),(40-45,0),(45-50,0),(50-55,2):}

Number series 34,30,28,24,22,18,…..

Find the modes of the following data. i) 5, 6, 3, 5, 4, 9, 5, 6, 4, 9, 5 ii) 25, 14, 18, 15, 17, 16, 19, 13, 12, 24 iii) 10, 15, 20, 15, 20, IO, 15, 20, 10

A student noted the number of cars passing through a spot on a road for 100 periods , each of 3 minutes , an summarised this in the table given below . {:("Number of cars","Frequency"),(0-10,7),(10-20,14),(20-30,13),(30-40,12),(40-50,20),(50-60,11),(60-70,15),(70-80,8):} Find the mode of the data .