Home
Class 14
MATHS
Consider the following statements: 1.Th...

Consider the following statements:
1.The algebraic sum of deviations of a set of values from their arithmetic mean is always zero.
2 Arithmetic mean `gt` median `gt` mode for a symmetric distribution
Which of the above statements are corrects?

A

A) 1only

B

B) 2only

C

C) Both 1 and 2

D

D) Neither I nor 2

Text Solution

AI Generated Solution

The correct Answer is:
To determine which of the given statements is correct, we will analyze each statement step by step. ### Statement 1: The algebraic sum of deviations of a set of values from their arithmetic mean is always zero. 1. **Definition of Arithmetic Mean**: The arithmetic mean (denoted as \( \bar{x} \)) of a set of values \( x_1, x_2, \ldots, x_n \) is calculated as: \[ \bar{x} = \frac{1}{n} \sum_{i=1}^{n} x_i \] 2. **Sum of Deviations**: We need to find the sum of deviations from the mean: \[ A = \sum_{i=1}^{n} (x_i - \bar{x}) \] 3. **Expanding the Sum**: We can expand the sum: \[ A = \sum_{i=1}^{n} x_i - \sum_{i=1}^{n} \bar{x} \] Since \( \bar{x} \) is constant for all \( n \) observations, we can rewrite the second term: \[ A = \sum_{i=1}^{n} x_i - n \cdot \bar{x} \] 4. **Substituting the Mean**: From the definition of the mean, we know that: \[ n \cdot \bar{x} = \sum_{i=1}^{n} x_i \] Therefore, substituting this into our equation for \( A \): \[ A = \sum_{i=1}^{n} x_i - \sum_{i=1}^{n} x_i = 0 \] 5. **Conclusion for Statement 1**: The algebraic sum of deviations from the arithmetic mean is indeed always zero. Thus, Statement 1 is **correct**. ### Statement 2: Arithmetic mean > Median > Mode for a symmetric distribution. 1. **Understanding Symmetric Distribution**: In a symmetric distribution, the mean, median, and mode are all equal. This means: \[ \text{Mean} = \text{Median} = \text{Mode} \] 2. **Analyzing the Inequality**: The statement suggests that the arithmetic mean is greater than the median, and the median is greater than the mode. However, since all three measures are equal in a symmetric distribution, this inequality does not hold. 3. **Conclusion for Statement 2**: Therefore, Statement 2 is **incorrect**. ### Final Conclusion: - **Statement 1** is correct. - **Statement 2** is incorrect. Thus, the answer is that only the first statement is correct.
Promotional Banner

Topper's Solved these Questions

  • STATISTICS

    PUNEET DOGRA|Exercise PRE YEAR QUESTIONS |163 Videos
  • SET & RELATION

    PUNEET DOGRA|Exercise PREV YEAR QUESTIONS|65 Videos
  • TRIGONOMETRY

    PUNEET DOGRA|Exercise PREV YEAR QUESTIONS|163 Videos

Similar Questions

Explore conceptually related problems

Consider the following statements: 1. The algebraic sum of deviations of a set of values from their arithmetic mean is always zero. 2. Arithmetic mean gt Median gt Mode for a symmetric distribution. Which of the above statements is/are correct?

The algebraic sum of the deviations of a set of n values from their mean is 0( b ) n-1 (c) n (d) n+1

Show that the sum of deviations of the values of the variable from their arithmetic mean is equal to zero.

The algebraic sum of the deviations of a set of n values from their mean is (a) 0 (b) n-1 (c) n( d) n+1

Consider the following statements: 1. The algebraic sum of the deviations of a set of n value from its arithmetic mean is zero. 2. In the case of frequency distribution, mode is the value of variable which corresponds to maximum frequency. Which of the statements above given is/are correct?

PUNEET DOGRA-STATISTICS-PRE YEAR QUESTIONS
  1. If two variables X and Y are independent, then what is correlation coe...

    Text Solution

    |

  2. the mean of 100 observations is 50 and the standard deviation is 10. I...

    Text Solution

    |

  3. Consider the following statements: 1.The algebraic sum of deviations ...

    Text Solution

    |

  4. Let the correlation coefficient between X and Y be 0.6, random variabl...

    Text Solution

    |

  5. If all the natural numbers between 1 and 20 are multiplied by 3, then ...

    Text Solution

    |

  6. In any discrete series (when all values are not sume) if x represents ...

    Text Solution

    |

  7. Which one of the following can be obtained from a histogram ?

    Text Solution

    |

  8. if x(1) gt 0,y(1) gt 0 (1,2 3…. n) are the values of two variable X ...

    Text Solution

    |

  9. The variance of 25 observations is 4. If 2 is added to each observatio...

    Text Solution

    |

  10. Consider the following statements: If 10 is added to each entry on ...

    Text Solution

    |

  11. The average age of a combined group of men and women is 25 years. If t...

    Text Solution

    |

  12. The correlation coefficient computed from a set of 30 observations is ...

    Text Solution

    |

  13. If the regression coefficient of Yon X is-6 and the correlation coeffi...

    Text Solution

    |

  14. The set of bivariate observations (x(1), y(1)), (x(2) y(2)).... (x(n) ...

    Text Solution

    |

  15. The standard deviation sigma of the first N natural numbers can be obt...

    Text Solution

    |

  16. A train covers the first Skm of its journey at a speed of 30km/hr and ...

    Text Solution

    |

  17. The mean and standard deviation of a set of values are 5 and 2 respect...

    Text Solution

    |

  18. In a test in Mathematics 20% of the students obtained first class If t...

    Text Solution

    |

  19. What is the median of a numbers 4.6, 0, 9.3.-4.8. 7.6. 23. 12.7.3.5, 8...

    Text Solution

    |

  20. Consider the following statements I. The sum of deviations from mean...

    Text Solution

    |