Question

if the mean of the observations a+1, a+3, a+5, a+7, a+9 is 9 find the mean of first 3 terms​

Answer 1

Given:-

observation :- (a+1),(a+5),(a+7),(a+9),(a+3).

Mean :- 9

To Find :-

Mean of first 3 terms.

Answer :-

7-> Is the mean of first 3 terms.

Step By Step Explaination :-

Mean = (Sum of Observations)/Total terms.

Now, Given that,.

=> 9 = (a+1)+(a+3)+(a+5)+(a+7)+(a+9)/5

=> 9= 5a+25/5

=>45=5a+25

=> 45-25=5a

=> 20/5=a

=> a= 4

Now, The first three terms are :-

=> 4+1,4+3,4+5

=> 5,7,9

Mean = (sum of observations/total no.)

=> Mean = 21/3

=> Mean = 7

So the mean is '7' .

Ans.

Answer 2

Answer:

hope this will help u ❤️