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:
    Example:
  • 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).
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:  Average=SumTotalnumberofobjects
 
              Average=666=11
Reference:
Reference Class 7 NCERT CBSE Book