Login Make a Donation

Average Rating

Formula for Average Rating

Calculating the average rating is straightforward and involves summing up all the individual ratings and then dividing by the total number of ratings.

Here’s the formula and a step-by-step explanation:



Average Rating=∑(Individual Ratings)Total Number of Ratings



Steps to Calculate Average Rating


Sum the Individual Ratings: Add up all the individual rating values.

Count the Total Number of Ratings: Determine how many ratings there are in total.

Divide the Sum by the Count: Divide the sum of the individual ratings by the total number of ratings.


Example:

Suppose you have the following ratings: 4, 5, 3, 4, 5.




Sum the Individual Ratings:

4+5+3+4+5=21


Count the Total Number of Ratings: 

There are 5 ratings.


Divide the Sum by the Count: 

Average Rating=215=4.2\text{Average Rating} = \frac{21}{5} = 4.2

=521​=4.2

So, the average rating is 4.2.


In a Tabular Data Example

If you have ratings data in a table:


Rating

4

5

3

4

5



Step-by-Step Calculation:


Step 1: Sum of ratings = 4 + 5 + 3 + 4 + 5 = 21
Step 2: Total number of ratings = 5
Step 3: Average rating = 21 / 5 = 4.2


How to Calculate the Missing Rating

To calculate a missing rating, we need to use the average rating formula and solve for the missing rating. Let's assume we know the desired average rating, the other individual ratings, and the total number of ratings, including the missing one.



Average Rating=∑(Individual Ratings) + Missing RatingTotal Number of Ratings



Steps to Calculate the Missing Rating

1. Identify the known variables:

- Average rating (A)
- Sum of known ratings (S)
- Total number of ratings (N)

2. Set up the equation:

A=S + Missing RatingN


3. Solve for the missing rating:

Missing Rating = A ×\times N − S


Example:

Suppose the desired average rating is 4.5, and we have the following ratings: 4, 5, 4. Let's assume there are 4 ratings in total, including the missing one.



1. Known Variables:

- Average rating (A) = 4.5
- Sum of known ratings (S) = 4 + 5 + 4 = 13
- Total number of ratings (N) = 4

2. Set up the equation:

4.5=13 + Missing Rating4


3. Solve for the missing rating:

13 + Missing Rating = 4.5 × 4
13 + Missing Rating = 18
Missing Rating = 18 − 13
Missing Rating=5


So, the missing rating is 5.

Verification

To verify, calculate the average with the missing rating:


Average Rating=4 + 5 + 4 + 5
4

 = 

184

 = 4.5








The calculated missing rating indeed results in the desired average rating.