It is the dimensions that are given in natural numbers or non-negative integers. So no fractions. Such as the room is 2x4 feet NOT the room is 2.5x 3.2 feet or 2 1/2 x 3 1/4 feet
8
You can work this out with long division, by checking to see if (x2 - 1) is a factor of (2x4 + 4x3 - x2 + 4x - 3). It is. Unfortunately, the WikiAnswers system is somewhat limited in depicting things such as long division, so we won't be able to represent it here. In short though, (2x4 + 4x3 - x2 + 4x - 3) / (x2 + 1) is equal to 2x2 + 4x - 3. which means that: (x2 + 1) / (2x4 + 4x3 - x2 + 4x - 3) = (x2 + 1) / (x2 + 1)(2x2 + 4x - 3) = 1 / (2x2 + 4x - 3)
2x4
17 2x4=8+(3x3)=17 3x3=9 9+8=17
2x4x20/12= 13.33 bdft.
Can be eight or eleven feet long. In actuality, it can be as long as you want. 2x4 refers to the width and height dimensions of the plank, not the length. So I could cut a 2x4 to 2 inches long and it would be a 2 inch long 2x4.
Linear footage as referred to in wood or lumber is the length as you see it.For instance a 2 x 4 x 8, is 8 feet long. - In theoretical board feet this is actually 5.333 board feet or practically, 5.0 board feet. ( because a 2x4 is not really that dimension, but 1.5x3.5. )
256 feet
A 2X4 would be a stud, not a board. Weight depends on the length and species, if it is pressure treated or not. 8ft. hem-fir 2X4 is about 8 pounds or so.
OH, and its about 7 feet high
20x20 = 400 2x4= 8 400/8= 50 needed
75
At 2x4x10 and spaced 2 feet apart, at least 70.
BF = nominal thickness" (t) x nominal width" (w) x linear feet'(LF)/ 12" then BFx12"/ (t)x(w)= LF so if you have 200 BF of 2x4 200'x12"/2"x4"= 2400/8= 300 LF of lumber
28
12' is max for a 2 x 4 wall. You will need 69 studs for a 90' wall with 16" centers.