### Theory:

You might be aware of the term average and would have come across statements involving the term average in your day-to-day life:

**Isha spends an average of about \(5\) hours daily for her studies.**(By average we understand that Isha, usually, studies for \(5\) hours. On some days, she may study for fewer hours, and on the other days, she may study longer).**The average temperature at this time of the year is about \(40°C\).**(The average temperature of \(40°C\) means that very often the temperature at this time of the year is around \(40°C\). Sometimes, it may be less than \(40°C\), and at other times it may be more than \(40°C\)).**The average age of pupils in my class is \(12\) years.**(A class may contain pupils who are less than or more than a certain age. In the example, the average age of the class is \(12\) years).**The average attendance of students in a school during its final examination was \(98\) percent.**(Not all the students attend the class regularly the average attendance of a particular session gives the central value of the attendance percentage).

Example:

Average :

An average is a number that represents or shows the central tendency of a group of observations or data. Since average lies between the highest and the lowest value of the given data so, we say the average is a measure of the central tendency of the group of data.

We can define average as the sum of total numbers divided by the total number of objects.

Example:

Get the average of the following set of numbers :

\(5,4,16,25,13,3.\)

**Step 1:**\(Sum = 5 +4 + 16 + 25 +13 + 3 = 66\)

**Step 2:**$\mathit{Average}\phantom{\rule{0.147em}{0ex}}=\phantom{\rule{0.147em}{0ex}}\frac{\mathit{Sum}}{\mathit{Total}\phantom{\rule{0.147em}{0ex}}\mathit{number}\phantom{\rule{0.147em}{0ex}}\mathit{of}\phantom{\rule{0.147em}{0ex}}\mathit{objects}}$

$\mathit{Average}\phantom{\rule{0.147em}{0ex}}=\phantom{\rule{0.147em}{0ex}}\frac{66}{6\phantom{\rule{0.147em}{0ex}}}=\phantom{\rule{0.147em}{0ex}}11$

Reference:

Reference Class 7 NCERT CBSE Book