conditional multiplication by column rate

Hi i have attached sample file with desired output. G, U, Q rate are fixed. if the value is in G it should be multiply by 5.3, if U by 3.7 and so on.

any formula other than this:

Formula:

=IF(B4<>"",B4*$B$2,IF(C4<>"",C4*$C$2,D4*$D$2))

and

Formula:

=SUMPRODUCT((1*(B4:D4<>""))*($B$2:$D$2)*($B$4:$D$6))