In mathematics and also statistics, steps of main tendencies explain the an introduction of whole data set values. The most crucial measures of main tendencies space mean, median, mode, and range. Amongst these, the average of the data set provides the overall idea the the data. The mean specifies the mean of number in the data set. The different species of median are Arithmetic typical (AM), Geometric mean (GM), andHarmonic Mean(HM). In Mathematics, theGeometric average (GM)is the median value or median which signifies the main tendency that the collection of numbers by recognize the product of their values. In this lesson, permit us discuss the definition, formula, properties, applications, the relation between AM, GM, and HM v solved instances in the end.

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1.Geometric average Definition
2.Geometric mean Formula
3.Difference between Arithmetic Mean and also Geometric Mean
4. Relation in between AM, GM, and also HM
5.Solved instances on Geometric Mean
6.Practice Questions
7.FAQs top top Geometric Mean

Geometric average Definition


TheGeometric typical (GM)is the average value or typical which signifies the central tendency the the collection of numbers by acquisition the source ofthe product of your values. Basically, we multiply the 'n' values altogether and also take out the nth root of the numbers, wherein n is the total variety of values. Because that example: because that a given set of 2 numbers such together 8and 1, the geometric mean is equal to√(8×1) =√8= 2√2.

Thus, the geometric typical is additionally defined as the nth source of the product the n numbers. The is come be provided that the geometric average is different from the arithmetic mean. Inthe arithmetic mean, data worths are included and climate dividedby the total variety of values. However in geometric mean,the provided data values are multiplied, and also then you take the root with the radical index because that the last productof data values. For example, if you have two data, take it the square root, or if you have actually three data, climate take the cube root, or else if girlfriend have 4 data values, then take the 4th root, and also so on.


Geometric mean Formula


The Geometric typical (G.M) of a data setcontaining n monitorings is the nth root of the product that the values. Consider, if \(x_1, x_2 \ldots . X_n\)are the observation, because that which us aim to calculate the Geometric Mean.The formula to calculate the geometric mean is given below:

GM = \(\sqrtx_1, x_2, \ldots x_n\)

or

GM = \(\left(x_1, x_2, \ldots x_n\right)^\frac1n\)

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This can also be written as;

\(\log \mathrmGM=\frac1n \log \left(x_1, x_2 \ldots x_n\right)\)

\(=\frac1n\left(\log x_1+\log x_2+\ldots+\log x_n\right)\)

\(=\frac\sum \log x_in\)

Therefore, Geometric Mean, GM =Antilog \(\frac\sum \log x_in\)

Where \(\mathrmn=\mathrmf_1+\mathrmf_2+\ldots . .+\mathrmf_\mathrmn\)

It is also represented as:

G.M. \(=\sqrt\prod_i=1^n x_i\)

For any Grouped Data, G.M deserve to be composed as;

\(\mathrmGM=\operatornameAntilog \frac\sum f \log x_in\)


Difference in between Arithmetic Mean and Geometric Mean


Here is a table representing the difference between arithmetic and geometric mean.

Arithmetic MeanGeometric Mean
In the arithmetic mean, data values are included and then dividedby the total number of values.Geometric Mean can be uncovered by multiplying every the numbers in the provided data collection and take the nth root for the acquired result.

For example, the provided data to adjust are:

10, 15 and also 20

Here, the number of data points = 4

Arithmetic mean or average = (10+15+20)/4

Mean = 45/3=15

For example, because that data set, 4, 10, 16, 24

Here n = 4

Therefore, the G.M = 4th root that (4×10×16×24)

= fourth root of 15360

G.M = 11.13


Relation in between AM, GM, and also HM


Before welearn the relation between the AM, GM and HM, we require to recognize the recipe of every these 3 varieties of mean. Assume that “a” and also “b” are the 2 number and the number of values = 2, then

⇒ 1/AM = 2/(a+b) ……. (I)

GM =(ab)

⇒GM2= abdominal ……. (II)

HM= 2/<(1/a) + (1/b)>

⇒HM = 2/<(a+b)/ab

⇒ HM = 2ab/(a+b) ….. (III)

Now, substitute (I) and also (II) in (III), we get

HM = GM2/AM

⇒GM2= AM×HM

Or else,

GM = √< to be × HM>

Hence, the relation between AM, GM, and also HM is GM2= AM×HM. Therefore the square the the geometric average is equal to the product of the arithmetic mean and also the harmonic mean.

Let us additionally see why the G.M for the provided data collection is always less 보다 the arithmetic typical for the data set. Allow A and also G it is in A.M. And also G.M.

So,

A = (a+b)/2andG=√ab

Now let’s subtract the two equations

A−G = (a+b)/2 − √ab = (a+b−2√ab)/2 = (√a−√b)2/2 ≥ 0

A−G ≥ 0

This suggests thatA ≥ G

Application of Geometric Mean

Geometric mean has many benefits over arithmetic mean and also it is supplied in many fields.Some that the applications are as follows:

It is supplied in share indexes due to the fact that many that the value line indexes which are offered by jae won departments exploit G.M.To calculate the annual return on the investment portfolio.The geometric average is supplied in finance to find the average expansion rates i m sorry are also known together the compounded annual growth rate (CAGR).Geometric mean is likewise used in biological studies favor cell division and bacterial expansion rateetc.

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Tips & tricks on Geometric Mean


Some of the tips and also tricks on G.M room as follows:

The G.M for the offered data collection is constantly less 보다 the arithmetic average for the data set.If each value in the data set is substituted through the G.M, then the product that the values continues to be unchanged.The ratio of the corresponding observations of the G.M in two series is same to the proportion of their geometric means.The assets of the equivalent items of the G.M in the two series are same to the product of your geometric mean.

See more: How Many Periods Are There In The Modern Periodic Table, (Periodic Table)


Example 3: discover the geometric mean of the adhering to grouped data for the frequency distribution of weights.

Weights the Cellphones (g)No of Cellphones (f)
60-8022
80-10038
100-12045
120-14035
140-16020
Total160

Solution:

Weights that Cellphones (g)No that Cellphones (f)Mid xLog xf log x
60-8022701.84540.59
80-10038901.95474.25
100-120451102.04191.85
120-140351302.11473.99
140-160201502.71643.52
Total160324.2

From the offered data, n = 160We understand that the G.M because that the grouped data is\(\mathrmGM=\operatornameAntilog \frac\sum f \log x_in\)GM =Antilog (324.2 / 160)GM = Antilog (2.02625)GM =106.23Therefore, the GM =106.23