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
S.D. of a data is 6. When each observation is increased by 1, then the S.D. of new data is
  • A
    6
    Correct
  • B
    5
  • C
    7
  • D
    8
2
The most stable measure of central tendency is
  • A
    mean
    Correct
  • B
    none of these
  • C
    mode
  • D
    median
3
The mean weight of a group of 10 items is 28 and that of another group of n items is 35.The mean of combined group of 10 + n items is found to be 30. The value of n is
  • A
    12
  • B
    2
  • C
    4
    Correct
  • D
    10
4
The measure of variation which is least affected by extreme items is
  • A
    quartile deviation
    Correct
  • B
    standard deviation
  • C
    mean deviation
  • D
    range
5
A group of 10 items has mean 6. If the mean of 4 of these items is 7.5, then the mean of the remaining items is
  • A
    5.0
    Correct
  • B
    4.5
  • C
    6.5
  • D
    5.5
6
If the coefficient of variation between x and y is 0.28, covariance between x and y is 7.6, and the variance of x is 9, then the S.D. of the y series is
  • A
    9.05
    Correct
  • B
    9.8
  • C
    10.1
  • D
    10.05
7
The Q.D. of the daily wages (in Rs) of 7 persons given below: 12,7,15,10,17,19,25 is
  • A
    4.5
    Correct
  • B
    9
  • C
    14.5
  • D
    5
8
Which of the following is not a measure of central tendency :
  • A
    median
  • B
    range
    Correct
  • C
    mean
  • D
    mode
9
If the mean of numbers 27,31,89,107,156 is 82 , then the mean of 130,126,68,50,1 is :
  • A
    82
  • B
    80
  • C
    75
    Correct
  • D
    157
10
If in moderately asymmetrical distribution mode and mean of the data are 6 \(\mu \) and 9 \(\mu \) respectively, then median is
  • A
    8 \(\mu \)
    Correct
  • B
    5 \(\mu \)
  • C
    7 \(\mu \)
  • D
    6 \(\mu \)
11
If the mean of the squares of first n natural numbers be 11, then n is equal to
  • A
    5
    Correct
  • B
    13
  • C
    - 13/ 2
  • D
    11
12
If the mean of the first n odd natural numbers be n itself, then n is equal to
  • A
    any natural number
    Correct
  • B
    2
  • C
    1
  • D
    3
13
The mean of the first n terms of the A.P. (a + d ) + ( a + 3d ) + ( a + 5d ) +………..is
  • A
    none of these
  • B
    \(a + {n \over 2}d\)
  • C
    a + nd
    Correct
  • D
    \(a + {n^2}d\)
14
If a, b, c be any three positive numbers, then the least value of \(\left( {a + b + c} \right)\left( {{1 \over a} + {1 \over b} + {1 \over c}} \right)is\)
  • A
    9
    Correct
  • B
    6
  • C
    3
  • D
    1
15
The median of the data 13,14,16,18,20,22 is
  • A
    17
    Correct
  • B
    16
  • C
    18
  • D
    19