I did say the answer is $35. Because, you should use the highest factor or whatever operation the problem is using, to find the answer. Not sure if it's some two-step problem....
So we're looking at two rectangles, one cut out of the other, so all you do is find the area of the big one, base times height equals area, minus the area of the small one, base times height equals area. So the equation you have to solve for is this,
Area=(12.6X14)-(3X8.4)
1/
V=44.312 in^3
2/
V=42.453 in^3
3/
V=75.36 in^3
4/
V=696.557 in^3
5/
V=671.175 in^3. Hope it help!