How to back into a weighted average?

[questionking]

I need help calculating a weighted average rate for a specific value. I know value 226 has a weighted average of 0.33920. How would I calculate this, given the criteria below? Thanks in advance for your help, it is much appreciated. 130 0.15000% 463 0.17245% 273 0.25000% 1,149 0.28097% 571 0.32188% 703 0.39686% 82 0.40522% 50 0.65000% 96 0.81901% 174 1.28639% 226 3,916 0.35689% <colgroup><col width="77" style="width: 58pt; mso-width-source: userset; mso-width-alt: 2816;"> <col width="108" style="width: 81pt; mso-width-source: userset; mso-width-alt: 3949;"> <tbody> </tbody>

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[RoryA]

Welcome to the forum.

Assuming that data is in A1:B12 and that the data means what I think it does, you would use:

=((B12*A12)-SUMPRODUCT(A1:A10,B1:B10))/A11

 

[questionking]

Thank you, that worked and checks out. Much appreciated!