Home
Class 10
MATHS
If x(i)'s are the mid-points of the clas...

If `x_(i)'s` are the mid-points of the class intervals of grouped data, `f_(i)'s` are the corresponding frequencies and `bar(x)` is the mean, then `sum(f_(i)x_(i)-bar(x))` equal to

A

1

B

0

C

-1

D

2

Text Solution

Verified by Experts

Clearly , we have `Sigma f_i(x_i-barx)=0`
Promotional Banner

Topper's Solved these Questions

  • MEAN,MEDAN,MODE OF GROUPED,DATA CUMULATIVE FREQUENCY GRAPH AND OGIVE

    RS AGGARWAL|Exercise MUTIPLE-CHOICE QUESTIONS (MCQ)|8 Videos

  • MEAN,MEDAN,MODE OF GROUPED,DATA CUMULATIVE FREQUENCY GRAPH AND OGIVE

    RS AGGARWAL|Exercise Test Yourself|18 Videos

  • MEAN,MEDAN,MODE OF GROUPED,DATA CUMULATIVE FREQUENCY GRAPH AND OGIVE

    RS AGGARWAL|Exercise Exercise 18F|9 Videos

  • LINEAR EQUATIONS IN TWO VARIABLES

    RS AGGARWAL|Exercise QUESTION|2 Videos

  • PERIMETER AND AREA OF PLANE FIGURES

    RS AGGARWAL|Exercise TEST YOURSELF (SHORT -ANSWER QUESTIONS)|1 Videos

Similar Questions

Explore conceptually related problems

If x_(i) ' s are the midpoints of the class intervals of grouped data, f_(i) 's are the corresponding frequencies and barx is the mean, then what is Sigma (f_(i)x_(i)-barx) equal to ?

If x_(i) 's are the mid-points of the class intervals of grouped data f_(i)'s are the corresponding frequencies and x is the mea, then sum(f_(i)x_(i)-x) is equal to

The average of n numbers x_(1), x_(2), ……. X_(n) is bar(x) . Then the value of sum_(i=1)^(n) (x_(1) - bar(x)) is equal to

Find the mean (bar(X)) if sumf_(i)x_(i)=75andsumf_(i)=15 .

The measurments ( in mm) of the diameters of the head of the screws are given below : Calculate the mean diameter of the screw by ' Assumed Mean Method' . Steps to calculate mean by this method : (1) Assume mean A. In this example , A = 40. (Generally, the class mark of the class having the maximum frequency or the class mark of the middle class is chosen as the assumed mean.) (2) In column 1, write the class intervals,(Here, diameter). (3) In column 2, write the corresponding class marks. (4) In column 3, write the value of d_(i), " where " d_(i) = x_(i) - A . A is the assumed mean. (5) In column 4, write the frequencies (f_(i)) . Write Sigma f_(i) at the bottom of this column. (6) In column 5, write the product (f_(i) xx d_(i)) and their sum Sigma f_(i) d_(i) . Calculate bar d " and " bar X using the following formulae : bard = (Sigma f_(i)d_(i))/(Sigma f_(i))." Mean" barX = A + bar d . [d : mean of deviations.]

If bar(X) is the mean of a distribution of X, then under usual notation sum sum_(i=1)^(n)f_(i)(x_(2)-bar(x)) is

RS AGGARWAL-MEAN,MEDAN,MODE OF GROUPED,DATA CUMULATIVE FREQUENCY GRAPH AND OGIVE -Multiple Choice Questions (Mcq)
  1. The mode of a frequency distribution is obtained graphically from

    Text Solution

    |

  2. The median of a frequency distribution is found graphically with the h...

    Text Solution

    |

  3. The cumulative frequency table is useful in determining the

    Text Solution

    |

  4. The abscissa of the point of intersection of the Less Than Type and of...

    Text Solution

    |

  5. If x(i)'s are the mid-points of the class intervals of grouped data, f...

    Text Solution

    |

  6. In the formula bar(x)=a+h(sumf(i)u(i))/(sumf(i)) for finding the mea...

    Text Solution

    |

  7. In the formula bar(x)=a+(sumf(i)d(i))/(sumf(i)) for finding the mean...

    Text Solution

    |

  8. While computing mean of grouped data, we assume that the frequecies ar...

    Text Solution

    |

  9. The relation between mean, mode and median is

    Text Solution

    |

  10. If the 'less than type' ogive and 'more than type' ogive intersect eac...

    Text Solution

    |

  11. MODE - Definition and How to calculate MODE of Distribution.

    Text Solution

    |

  12. Median=

    Text Solution

    |

  13. If the mean and median of a set of numbers are 8.9 and 9 respectively...

    Text Solution

    |

  14. The mean and mode of a frequency distribution are 28 and 16 respective...

    Text Solution

    |

  15. The median and mode of a frequency distribution are 26 and 29 respect...

    Text Solution

    |

  16. For a symmetrical frequency distribution , we have

    Text Solution

    |

  17. The median of first 8 prime numbers is

    Text Solution

    |

  18. The average of 20 numbers is zero. Of them, at the most how many may b...

    Text Solution

    |

  19. If the median of the data 4,7,x-1,x-3,16,25, written in ascending orde...

    Text Solution

    |

  20. The mean of 2,7,6 and x is 5 and the mean of 18,1,6,x and y is 10 What...

    Text Solution

    |