Following are the marks obtained by 25 students in economics.
Find out the mean marks by using Direct and Short-cut Method.
`{:("Marks",10,20,30,40,50,60),("Number of Students",5,2,3,8,4,3):}`

Distribution of marks obtained by 100 student of a class is given below . Find out the median marks {:("Marks",0,5,10,15,20,25,30,35,40,45),("Number of Students",4,6,15,5,8,12,28,14,3,5):}

Find the mean for the following data. {:("Marks obtained",10-20,20-30,30-40,40-50,50-60,60-70),("Number of students",8,6,12,5,2,7):}

The following table gives the marks obtained by some students. Calculate the median marks obtained by the students. {:("Marks",0-5,5-10,10-15,15-20,20-25,25-30,30-35,35-40,40-45),("Number of Students"," "6," "12," "17," "30," "10," "10," "8," "5," "2):}

Find out median marks from the following data : {:("Marks",0-10,10-20,20-30,30-40,40-50),("Number of Students"," "8," "30," "40," "12," "10):}

Following is the pocket allowance of 10 students. Find out arithmetic mean using Short-cut Method. {:("Pocket Allowance(Rs.)",15,20,30,22,25,18,40,50,55,65):}

The following table shows marks in English secured by students of Class X in your school in their examination. Calculate mean marks using Direct Method. {:("Marks",0-10,10-20,20-30,30-40,40-50),("Number of Students"," "20," "24," "40," "36," "20):}

The following table shows marks obtained by the students of a class in their test in English: {:("Marks",0-10,10-20,20-30,30-40,40-50),("Number of Students"," "20," "24," "40," "36," "20):} Calculate arithmetic mean using Step-deviation method.