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 2x + y =7 and x + 2y = 7, then \(\rho \left( {X,Y} \right)\) is equal to
  • A
    - 1/ 2
    Correct
  • B
    1/ 4
  • C
    1/ 2
  • D
    none of these
2
The mean of 50 observations is 36, if two observations are 30 and 42 are deleted , then the mean of the remaining observations is
  • A
    36
    Correct
  • B
    38
  • C
    48
  • D
    46
3
For a bivariate frequency distribution \({b_{yx}} > 1,\) then \({b_{yx}}\)is
  • A
    lies between 0 and 1
    Correct
  • B
    less than 1
  • C
    none of these
  • D
    negative
4
A man tavels at a speed of 20 km/hour and then return at a speed of 30 km/hour. His average speed of the whole journey is
  • A
    24.5 km/hour
  • B
    25 km/hour
  • C
    26 km/hour
  • D
    24 km/hour
    Correct
5
The S.D. of the first n natural numbers is
  • A
    \(\sqrt {{{{n^2} - 1} \over {12}}} \)
    Correct
  • B
    \({{n + 1} \over 2}\)
  • C
    \(\sqrt {{{n(n + 1)} \over 2}} \)
  • D
    none of these
6
In a group of students, mean weight of boys is 80 kg and mean weight of girls is 50kg.If the mean weight of all the students taken together is 60kg, then the ratio of the number of boys to that of the girls is
  • A
    3 \(:\) 2
  • B
    2 \(:\) 1
  • C
    2 \(:\) 3
  • D
    1 \(:\) 2
    Correct
7
If the mean of 3,4,x,7,10, is 6 , then the value of x is
  • A
    7
  • B
    5
  • C
    6
    Correct
  • D
    4
8
For a normal distribution, we have
  • A
    median = mode
  • B
    mean = mode
  • C
    mean = median = mode
    Correct
  • D
    mean = median
9
The G.M. of the numbers 4,8,16 is
  • A
    8
    Correct
  • B
    28/ 7
  • C
    28/ 3
  • D
    28
10
The H.M. of the numbers 2,3,4 is
  • A
    13
  • B
    13/ 36
  • C
    36/ 13
    Correct
  • D
    3
11
If two variables X and Y are connected by the relation 2x + y = 3 , then \(\rho \left( {X,Y} \right)\) is equal to
  • A
    - 1
    Correct
  • B
    2
  • C
    - 2
  • D
    1
12
The variance of 2,4,6,8,10 is
  • A
    4
  • B
    8
    Correct
  • C
    6
  • D
    7
13
The S.D.of 7 scores 1,2,3,4,5,6,7, is
  • A
    2
    Correct
  • B
    4
  • C
    1
  • D
    -1
14
A data consists of two 2’s, four 4’s, six 6’s, three 8’s and 10. The mode of the data is
  • A
    6
    Correct
  • B
    4
  • C
    10
  • D
    2
15
The two lines of regression can never be
  • A
    parallel
    Correct
  • B
    perpendicular
  • C
    coincident
  • D
    intersecting