JEE Main Questions
Find the mean and variance for the following frequency distributions :
The following frequency distribution gives the monthly consumption of electricity of 68 consumers of a locality. Find the median, mean and mode of the data and compare them.
|No. of consumers||4||5||13||20||14||8||4|
The table below shows the daily expenditure on food of 25 households in a locality.
|Daily expenditure (in Rs.)||100-150||150-200||200-250||250-300||300-350|
|Number of households:||4||5||12||2||2|
Let x1,x2,x3,, be n values of a variable X. If these values are changed to x1+a,x+2+a,,xn+a,wherea∈R, show that the variance remains unchanged.
The distribution below gives the weights of 30 students of a class. Find the median weight of the students.
Calculate the missing frequency from the following distribution, it being given that the median of the distribution is 24.
Calculate mean deviation from the median of the following data: Class interval: 0-6 6-12 12-18 18-24 24-30 Frequency 4 5 3 6 2