While computing mean of grouped data, we assume that the frequencies are
a. evenly distributed over all the classes
b. centred at the classmarks of the classes
c. centred at the upper limits of the classes
d. centred at the lower limits of the classes

Solution:

While computing mean of grouped data, we assume that the frequencies are centred at the classmarks of the classes

Therefore, the frequencies are centred at the classmarks of the classes.

✦ Try This: Write the formula to find mean for grouped data direct method.

Mean x = Σf_iu_i/Σf_i

Where

fi is the frequency for that particular class

ui is the mid point of that particular class

Therefore, the formula to find the mean is \(\overline{x}\) = Σf_iu_i/Σf_i.

☛ Also Check: NCERT Solutions for Class 10 Maths Chapter 14

NCERT Exemplar Class 10 Maths Exercise 13.1 Problem 2

While computing mean of grouped data, we assume that the frequencies are a. evenly distributed over all the classes, b. centred at the classmarks of the classes, c. centred at the upper limits of the classes, d. centred at the lower limits of the classes

Summary:

While computing the mean of grouped data, we assume that the frequencies are centred at the classmarks of the classes

☛ Related Questions:

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