Question

1. If 1, 2, … , are values in a variable such that ∑ ( − 2) = 110
=1
and ∑ ( − 5)

=1
= 20.
Find the value of and its mean.

Answer 1

Answer:

Step-by-step explanation:

Answer : value of n is 30 and Mean is 17/3

Step-by-step explanation :

( Please refer to attachment )

Questions might arrise in your mind -

Q. Why 110 = ∑ - 2n?

Ans. In ( x1 - 2 ) + ( x2 - 2 ) +.....+ ( xn - 2 ), there was 2 subtracted from each term.

Since there are n number of terms so - 2n is subtracted from Summation ( S ) or ∑

Q. What is Bar(X)?

Ans. Bar(X) is symbol of mean. Formula of Mean is,

Bar(X) = (1/n) ∑

Q. What ∑ stands for?

Ans. ∑ means Sigma used as symbol of Summation (S) to denote sum of n number of terms.

∑ = x1 + x2 +..... + xn