Weighted Mean

Authors

Affiliations

Nate Yomogida, B.S., SPT

Doctor of Physical Therapy

B.S. in Kinesiology

Chloë Kerstein, B.S., SPT

Doctor of Physical Therapy

B.A. in Neuroscience

Significance

Weighted means are very common in statistics, especially when studying populations.

Calculation

Weighted mean for percentages

• Exam 1: 15 % of your grade
• Exam 2: 40 % of your grade
• Exam 3: 45 % of your grade

Exam grades:

• Exam 1 Grade: 80%
• Exam 2 Grade: 90%
• Exam 3 Grade: 100%

What is your final weighted average for the class?

Step 1: Multiply the numbers in your data set by the weight

$$\text{Weight of an exam}=\text{Exam Weight}\times \text{Exam Grade}$$

$$\text{Weight of Exam 1}=(0.15)\times (0.80)$$