The mean of five observations is 5 and their variance is 9.20. If three of the given five observations are 1, 3 and 8, then a ratio of other two observations is :
(a)
4 : 9
(b)
6 : 7
(c)
5 : 8
(d)
10 : 3
The mean of five observations is 5 and their variance is 9.20. If three of the given five observations are 1, 3 and 8, then a ratio of other two observations is :
(a)
4 : 9
(b)
6 : 7
(c)
5 : 8
(d)
10 : 3
Question ID - 56844 | SaraNextGen Top Answer
The mean of five observations is 5 and their variance is 9.20. If three of the given five observations are 1, 3 and 8, then a ratio of other two observations is :
(a)
4 : 9
(b)
6 : 7
(c)
5 : 8
(d)
10 : 3
|
The mean of five observations is 5 and their variance is 9.20. If three of the given five observations are 1, 3 and 8, then a ratio of other two observations is : |
|||
|
(a) |
4 : 9 |
(b) |
6 : 7 |
|
(c) |
5 : 8 |
(d) |
10 : 3 |
1 Answer
127 votes
Answer Key / Explanation : (a) -
Let two observations are 
mean=
=5 ⇒1 +3 +8 +
⇒ 
variance 
⇒ 
⇒ 
….(2)
by (1) & (2)
= 97
Or 
127 votes
Answer Link
127