Question

Arithmetic mean of data x:1 2 3....n,f:1 2 3....n is

Answer 1

Answer:

(n+1)/2

Step-by-step explanation:

sum of 'n' natural numbers=n(n+1)/2

arithmetic mean=sum of all no.s/no. of all numbers

sum of all no.s=n(n+1)/2

total no. of numbers=n

arithmetic mean=[n(n+1)/2]/n

=n(n+1)/2n

arithmetic mean=(n+1)/2

Answer 2

Answer:

Step-by-step explanation:

Arithmetic mean of the data = ΣFiXi / ΣFi

= 1(1) + 2(2) + 3(3) + ........... n(n) / 1 + 2 + 3 + ........ n

= n(n+1)(2n+1)/6 / n(n+1)/2

= 2n+1/3