I'm trying to get a weighted average of columns E & H but only if the values
in column C match the values in column K. I tried nesting Sumif function
within sumproduct but this isn't working, it's just giving me a sum of colmn
H, not the weighted average. Any help would be appreciated.

=SUMPRODUCT(SUMIF($C$3:$C$320,K3,$E$3:$E$320),SUMI F($C$3:$C$320,$K3,$H$3:$H$320))/SUMIF($C$3:$C$320,K3,$E$3:$E$320)