How to Calculate Weighted Average

Step-by-Step Guide

1. 1

   Step 1: Sit down with your data

   You may need to read a report or story problem to recognize the numbers and their weights before doing the problem.
2. 2

   Step 2: a piece of paper and a pencil.

   It is usually faster to multiply percentages with a calculator. , You may want to write them down on your paper in a chart form.
   
   For example, if you are trying to figure out a grade, you should identify what you were graded on each exam. , This is often a percentage.
   
   List the weight next to the number.
   
   Percentages are common because weights are often a percentage of a total of
   100.
   
   If you are figuring out the weighted average of grades, investments and other financial data, look for the percentage of the occurrence out of
   100.
   
   If you are figuring the weighted average of grades, you should identify the weight of each exam or project. , Always multiply decimals by decimals, instead of decimals by percentages. , You can choose to write this at the end of the chart or to do it on 1 line, in a formula.
   
   For example, if you are trying to figure out the weighted average of certain grades, you might write
   0.9(0.25) to indicate a 90 percent grade times 25 percent of the total grade. , For example,
   0.9(0.25) +
   0.75(0.50) +
   0.87(0.25).
   
   The total weighted score for the class would be
   0.8175. , Continue reading to adjust the weighted average for different types of weights. , In our grade example, this is
   81.75 percent. , Identify a numerical weight for each number value.
   
   Multiply the number by the weight, just as you did with percentages. ,,, The answer is the average value for each number.
3. 3

   Step 3: Grab a calculator.

4. 4

   Step 4: Identify the numbers that are weighted.

5. 5

   Step 5: Identify the weights of each number.

6. 6

   Step 6: Convert percentages to decimals.

7. 7

   Step 7: Multiply each number by its weight.

8. 8

   Step 8: Add the weighted scores together.

9. 9

   Step 9: Note that the weights should total 100 if you are using percentages.

10. 10

    Step 10: Multiply by 100 to get the percentage.

11. 11

    Step 11: Adjust your formula for an answer that does not include percentages.

12. 12

    Step 12: Add together the values after you have multiplied them by their weights.

13. 13

    Step 13: Add together the weights for each value.

14. 14

    Step 14: Divide the total of the values by the total of the weights.

Detailed Guide

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