Home » (begin{array}{c|c} x & 1 & 2 & 3 & 4 & 5 \ hline f…

(begin{array}{c|c} x & 1 & 2 & 3 & 4 & 5 \ hline f…

(begin{array}{c|c} x & 1 & 2 & 3 & 4 & 5 \ hline f & 2 & 1 & 2 & 1 & 2end{array})
Find the variance of the frequency distribution above
  • A.
    (frac{3}{2})
  • B.
    (frac{9}{4})
  • C.
    (frac{5}{2})
  • D.
    3
Correct Answer: Option B
Explanation

(begin{array}{c|c} x & f & fx & bar{x} – x & (bar{x} – x)^2 & f(bar{x} – x)^2 \ hline 1 & 2 & 2 & -2 & 4 & 8\ 2 & 1 & 2 & -1 & 1 & 1\ 3 & 2 & 6 & 0 & 0 & 0\ 4 & 1 & 4 & 1 & 1 & 1\ 2 & 2 & 10 & 2 & 4 & 8\ hline & 8 & 24 & & & 18 end{array})
x = (frac{sum fx}{sum f})
= (frac{24}{8})
= 3
Variance (62) = (frac{sum f(bar{x} – x)^2}{sum f})
= (frac{18}{8})
= (frac{9}{4})