Q. 195.0( 1 Vote )

# Find the mean, me

For equal class intervals, we will solve by finding mid points of these classes using direct method.

We have got

Σfi = 50 and Σfixi = 1500

mean is given by

Thus, mean is 30.

To find median, Assume

Σfi = N = Sum of frequencies,

h = length of median class,

l = lower boundary of the median class,

f = frequency of median class

and Cf = cumulative frequency

Lets form a table.

We have got

So, N = 50

N/2 = 50/2 = 25

The cumulative frequency just greater than (N/2 = ) 25 is 39, so the corresponding median class is 30 - 40 and accordingly we get Cf = 24(cumulative frequency before the median class).

Now, since median class is 30 - 40.

l = 30, h = 10, f = 15, N/2 = 25 and Cf = 24

Median is given by,

= 30 + 0.67

= 30.67

Thus, median is 30.67.

Since, we have got mean = 30 and median = 30.67

Applying the empirical formula,

Mode = 3(Median) – 2(Mean)

Mode = 3(30.67) – 2(30)

Mode = 92.01 – 60 = 32.01

Mean = 30, Median = 30.67 and Mode = 32.01

Rate this question :

How useful is this solution?
We strive to provide quality solutions. Please rate us to serve you better.
Related Videos
Resources and Development Revision28 mins
Cube and Cuboid41 mins
History - Concept and Questions57 mins
Sphere and Hemisphere16 mins
Heights and Distances-I45 mins
Corrosion: Types, Pros and Cons41 mins
Right Circular Cylinder45 mins
Right Circular Cone And Frustum43 mins
Revision on Substitution and Elimination Method44 mins
Electric Motor37 mins
Try our Mini CourseMaster Important Topics in 7 DaysLearn from IITians, NITians, Doctors & Academic Experts
Dedicated counsellor for each student
24X7 Doubt Resolution
Daily Report Card
Detailed Performance Evaluation
view all courses