Statistics CBSE Questions & Answers

Statistics

This is Mathematics Class 11 Statistics CBSE Questions & Answers. There are 15 questions in this test with each question having around four answer choices.

Questions & Answers

1
If the two lines of regression are at right angles , then \(\rho \left( {X,Y} \right)\) is equal to
  • A
    1
  • B
    1 or - 1
  • C
    - 1
  • D
    0
    Correct
2
If COV(X,Y) = 0 , then the two lines of the regression are
  • A
    none of these
  • B
    parallel
  • C
    at right angles
    Correct
  • D
    coincident
3
If the variance of the data is V, then its S.D. is
  • A
    \(\sqrt V \)
    Correct
  • B
    ±\(\sqrt V \)
  • C
    \(V{^2}\)
  • D
    - \(\sqrt V \)
4
If the two lines of regression are y = 3x – 5 and y = 2x – 4 , then \(\rho \left( {X,Y} \right)\) is equal to
  • A
    \(\sqrt {{2 \over 3}} \)
    Correct
  • B
    \(\sqrt {{3 \over 2}} \)
  • C
    \(\sqrt {{1 \over 6}} \)
  • D
    )none of these
5
If the median = (mode + 2 mean) \(\mu \), then \(\mu \) is equal to
  • A
    3
  • B
    2
  • C
    1/ 3
    Correct
  • D
    2/ 3
6
If mean = ( 3 median – mode ) x , then the value of x is
  • A
    3/ 2
  • B
    1/ 2
    Correct
  • C
    1
  • D
    2
7
Least square lines of regression give best possible estimates , when \(\rho \left( {X,Y} \right)\) is equal to
  • A
    1/ 2
  • B
    less than 1
  • C
    - 1 or 1
    Correct
  • D
    greater than -1
8
\(\rho \left( {X,Y} \right)\) is equal to
  • A
    \({{COV(X,Y)} \over {VAR\left( X \right)VAR\left( Y \right)}}\)
  • B
    none of these
  • C
    COV(X,Y)
  • D
    \({{COV(X,Y)} \over {\sqrt {VAR(X)} \sqrt {VAR(Y)} }}\)
    Correct
9
Quartile deviation is nearly equal to
  • A
    2/ 3 \(\sigma \)
    Correct
  • B
    2/ 3 \(\sigma \)
  • C
    2 \(\sigma \)
  • D
    3/ 2 \(\sigma \)
10
For a symmetrical distribution \({Q_1} = 20\) and \({Q_{3.}} = 40\). The median of the data is
  • A
    20
  • B
    30
    Correct
  • C
    40
  • D
    10
11
Which of the following is not a measure of dispersion ?
  • A
    mean deviation
  • B
    mean
    Correct
  • C
    range
  • D
    variance
12
The mean and S.D. of 1,2,3,4,5,6 is
  • A
    \({7 \over 2},\sqrt {{{35} \over {12}}} \)
    Correct
  • B
    \({7 \over 2},\sqrt 3 \)
  • C
    3, 35/12
  • D
    3,3
13
The range of the following set of observations 2,3,5,9,8,7,6,5,7,4,3 is
  • A
    6
  • B
    7
    Correct
  • C
    11
  • D
    5.5
14
Which of the following, in case of a discrete data, is not equal to the median?
  • A
    5 \(^{{\rm{th}}}\) decile
  • B
    50 \(^{{\rm{th}}}\) percentile
  • C
    \({{\rm{2}}^{{\rm{nd}}}}\) quartile
  • D
    lower quartile
    Correct
15
Mean deviation from the mean for the observations – 1 , 0 ,4 is
  • A
    2/ 3
  • B
    2
    Correct
  • C
    3/ 2
  • D
    none of these