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):}`

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):}

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 median of the following data is {:("Marks obtained ","No. of students "),("less than 20",0),("less than 30",4),("less than 40",16),("less than 50",30),("less than 60",46),("less than 70",66),("less than 80",82),("less than 90",92),("less than 100",100):}

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):}

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.

Find 20% less than Rs70