# Excel: Can an array formula reliably do this kind of totaling?

I want to sum (by month) sales by person and multiply by the price to get total sales by month. I thought something like {=SUM(SUM(B5:E12)*G5:G12)} or just plain {=SUM(B5:E12)*G5:G12} would work, but it doesn't, as you can see in the cell identified as "Wrong". The cell marked "Right" is a simple sum of the extended products above it--I added the sales in weeks 1 thru 4 then multiplied the total by the price for each row. Is there an array formula or some other approach that won't involve extra/hidden rows to accomplish the task? It needs to span blank rows and text without blowing up. In a test, I essentially created the Red Team block and was able to get the correct answer. However, it may have been dumb luck--once I edited or added to it so that it was more realistic like what I've shown here it quit working. I'm trying to avoid a normal formula like =sum(B5:E5)*G5+sum(B6:E6)* G6+.... as there are quite a few rows an this becomes immediately tedious. Of course, if you have some other slick way of doing this, I'd be happy to see that too! Excel 2010

ABCDEFGHI
1Sales
2Jan   Price
3wk1wk2wk3wk4JanExt Jan
4Red Team
5Joe1111520
6Mary2929244
7Fred5544590
8
9Blue Team0
10Jane1233654
11Marge5633351
12Kevin89335115
13
142418<< WrongRight>>374

Sheet1