निम्न बारम्बारता बंटन का समान्तर माध्य ज्ञात करो :
`{:("वर्ग अन्तराल: ",0-20,20-40,40-60,60-80,80-100),("बारम्बारता:"," "15," "18," "21," "29," "17):}`

Explanation

माना कल्पित माध्य A = 50 तथा h = 20 है

स्पष्ट है की
`A = 50 , h = 20 , N= 100 "तथा " sum f_(i) u_(i) = 15`
` therefore overline (X) = A h {(1)/(N) sumf_(i)u_(i)} `
` rArr overline(X) = 50 + 20 xx(15)/(100)`
` rArr overline(X) = 50 3 = 53 `