Home
Class 10
MATHS
In Calculating the mean of grouped data,...

In Calculating the mean of grouped data, grouped in classes of equal width, we may use the formula
`bar(x)=a+(sumf_(i)d_(i))/(sumf_(i))`
Where, a is the assumed mean, a must be one of the mid point of the classes. Is the last statement correct? Justify your answer.

Text Solution

Verified by Experts

No, it is necessary that assumed mean consumed as the mid point of the class interval. It is considered as any value which is easy to simple it.
Promotional Banner

Topper's Solved these Questions

  • STATISTICS AND PROBABILITY

    NCERT EXEMPLAR|Exercise VERY SHORT ANSWERS QUESTIONS|2 Videos

  • STATISTICS AND PROBABILITY

    NCERT EXEMPLAR|Exercise LONG ASWERS QUESTIONS|5 Videos

  • REAL NUMBERS

    NCERT EXEMPLAR|Exercise Real Numbers|39 Videos

  • SURFACE AREAS AND VOLUMES

    NCERT EXEMPLAR|Exercise Surface Areas And Volumes|62 Videos

Similar Questions

Explore conceptually related problems

In the formula bar(x)=a+(sumf_(i)d_(i))/(sumf_(i)) for finding the mean of grouped data d_(i) 'S and deviation from a of

In the formula bar(x)=a+h(sumf_(i)u_(i))/(sumf_(i)) for finding the mean of grouped frequency distribution u_(i) is equal to

Choose the correct answer from the given four options: In the formula x=a+(sumx_(1)d_(i))/(sumf_(i)) for finding the mean of grouped data d_(i) 's are the deviations from a of

For the frequency distribution of time ( in minutes ) a worker takes to complete the work, sumf_(i)=100,sumf_(i)d_(i)=185 and mean (bar(X))=38.85 Find the assumed mean (A).

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 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.]

Find the correct answer from the alternative given : The formula to find mean from a grouped frequency table is barX = A + (Sigma f_(i)u_(i))/(Sigmaf_(i))xxg In the formula , u_(i) = ….

These questions consists of a question and two statements numbered I and II given below it. You have to decide whether the data provided to the statements are sufficient to answer the question. Read both the statements and select the appropriate answer How many students are there in the class? I. There are more than 20 but less than 27 students in the class. II. There are more than 24 but than 31 students in the class. The number of students in the class can be divided into groups such that each group contains 5 students.