# Math Help - Calculate Weighted Average

1. ## Calculate Weighted Average

Would it be correct to calculate the weighted average of the following scores by multiplying the score by the weight for all and then adding this up, or am I supposed to divide by something?

Ex.

Intern had 4 rotations worth 20% of overall score

Score %
R1 4 20%
R2 4 20%
R3 3 20%
R4 3 20%

there are 10 teammate qualities/dimensions that they are rated on
Score % Weight
D1 4 2%
D2 4 2%
D3 4 2%
D4 3 2%
D5 5 2%
D6 4 2%
D7 4 2%
D8 3 2%
D9 4 2%
D10 4 2%

Would I find the weighted avg by doing the following?:

(R1*.2)+(R2*.2)+(R3*.2)+(R4*.2)+(D1*.2)+(D2*.2)... ..+(D10*.2)

Thanks

2. Originally Posted by DKRbella0814
Would I find the weighted avg by doing the following?:

(R1*.2)+(R2*.2)+(R3*.2)+(R4*.2)+(D1*.2)+(D2*.2)... ..+(D10*.2)

Thanks
Almost. The D's should be multiplied by .02.
(R1*.2)+(R2*.2)+(R3*.2)+(R4*.2)+(D1*.02)+(D2*.02).....+(D10*.02)

3. Originally Posted by eumyang
Almost. The D's should be multiplied by .02.
(R1*.2)+(R2*.2)+(R3*.2)+(R4*.2)+(D1*.02)+(D2*.02).....+(D10*.02)
Here the weights sum to 1 so the above is OK, but in general they wont and you wiould need to divide the above by the sum of the weights.

CB