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

Let two observations are

mean==5 ⇒1 +3 +8 +

⇒

variance

⇒

⇒ ….(2)

by (1) & (2)

= 97

Or

127 votes

127