Weighted average is a calculation that takes into account the varying degrees of importance of the numbers in a data set.
One advantage of using the weighted average method is consistency.
Formula to calculate weighted average method.
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Example:
Suppose you scored 30% in assignments that account for 10% of your final grade and you then scored 80% in your final exam that accounts for 70% of your final grade. Calculate your weighted average of your grade.
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Thus, your weighted average is 29.5.