Another Tiered Pricing question

Hi,
I'm obviously an excel simpleton because I am failing miserably to design a tiered pricing structure, even though I've read as much as google has to offer on the matter.

The Units are G3:G12
12
24
36
48
132
252
492
1212
1812
2400

The corresponding prices are H3:H12
15
13.8
13.4
13
12.25
11.5
10.7
9.8
9.2
8.5

I need to have a cell that shows the price that has been 'selected' and a total cost.

Please, please could someone help me write this? I'm sure it's far less complicated than I've managed to make it!

I think I may love you just a little! Thank you very much. I was getting muddled with SUMPRODUCT and hadn't even considered a simpler solution!

Thank you thank you thank you!