Mean of a frequency distribution `(bar(x)) " is " 45`. If `Sigma f_(i) = 20 " find " Sigma f_(i) x_(i)`

Find the value of the mean barX , " if " Sigma f_(i) x_(i) = 30 " and " Sigma f_(i) = 6 .

Fine bar( u) , if Sigma f_(i) u_(i ) 252 and Sigmaf_(i) = 420

In a frequency distribution , if a =assumed mean = 55 , sumf_(i) = 100 , h = 10 and sumf_(i)mu_(i)= -30 , then find the mean of the distribution.

If the mean of a frequency distribution is 8.1 and sumf_i x_i=132+5k ,\ \ sumf_i=20 , then k= (a) 3 (b) 4 (c) 5 (d) 6

The mean of a discrete frequency distribution x_i//f_i ; i=1,\ 2,\ ddot,\ n is given by (a) (sumf_i x_i)/(sumf_i) (b) 1/n\ sum_(i=1)^nf_i x_i (c) (sumi=1nf_i x_i)/(sumi=1n x_i) (d) (sumi=1nf_i x_i)/(sumi=1n i)

The standard deviation (sigma) of variate x is the square root of the A.M. of the squares of all deviations of x from the A.M. observations. If x_i//f_i , i=1,2,… n is a frequency distribution then sigma=sqrt(1/N Sigma_(i=1)^(n) f_i(x_i-barx)^2), N=Sigma_(i=1)^(n) f_i and variance is the square of standard deviation. Coefficient of dispersion is sigma/x and coefficient of variation is sigma/x xx 100 For a given distribution of marks mean is 35.16 and its standard deviation is 19.76 then coefficient of variation is

The standard deviation (sigma) of variate x is the square root of the A.M. of the squares of all deviations of x from the A.M. observations. If x_i//f_i , i=1,2,… n is a frequency distribution then sigma=sqrt(1/N Sigma_(i=1)^(n) f_i(x_i-barx)^2), N=Sigma_(i=1)^(n) f_i and variance is the square of standard deviation. Coefficient of dispersion is sigma/x and coefficient of variation is sigma/x xx 100 The standard deviation for the set of numbers 1,4,5,7,8 is 2.45 then coefficient of dispersion is

Find the value of Sigma f_(i) for the following information : (i) Sigma f_(i)d_(i) = 800, bard = 8 " "(ii) Sigma f_(i)d_(i) = - 260, bar d = - 3.25

Find the value of bar u for the following information : (i) A = 22.5 , x_(i) = 27.5 , g = 5 " "(ii) Sigma f_(i)u_(i) = 54 , Sigma f_(i) = 120

If the mean of the following frequency distribution is 5, then b = {:(x_(i) " :",3,5,7,4),(f_(i)" :",2,a,5,b):}