Marks in Statistics of the students of Class XI are given below.
Find out arithmetic mean.
`{:("Marks",,"Number of Students"),("Less than 10",," "5),("Less than 20",," "17),("Less than 30",," "31),("Less than 40",," "41),("Less than 50",," "49):}`

The following table shows marks in economics of the students of a class. Calculate arithmetic mean. {:("Marks",,"Number of Students"),("More than 0",," "30),("More than 2",," "28),("More than 4",," "24),("More than 6",," "18),("More than 8",," "10):}

Calculate arithmetic mean , median and mode of the following series : {:("Marks",,"Number of Students"),("Less than 10",," "12),("Less than 20",," " 26),("Less than 30",," "40),("Less than 40",," "58),("Less than 50",," "80),("Less than 60",," "110),("Less than 70",," "138),("Less than 80",," "150):}

Calculate mode from the following data : {:( "Wages (Rs.)",,"Number of Workers"),("Less than 10",," "15),("Less than 20",," "35),("Less than 30",," "60),("Less than 40",," "84),("Less than 50",," "96),("Less than 60",," "127),("Less than 70",," "198),("Less than 80",," "250):}

I.Q.s of 100 students are given in the following less than type cumulative frequency distrbution : {:(" I.Q. ","Number of students "),("Less than 110 "," "0),("Less than 120 "," "10),("Less than 130 "," "29),("Less than 140 "," "64),("Less than 150 "," "78),("Less than 160 "," "90),("Less than 170 "," "100):} Obtain the cumulative frequency distribution of more than type for the data.

Construct a frequency table from the following data {:("Marks","No of students"),("less than" 10,6),("less than" 20,15),("less than" 30,30),("less than" 40,39),("less than" 50,53),("les than" 60,70):}