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# Algebra/Number Needed

Question
Hi Scott,

A deck is to be built using 2x4's 8 feet long.

Dimensions of deck- 30 feet long, 8 feet wide with 3/8" spacing.

The last board could be cut lengthwise to fit if necessary, resulting in a smaller width board and would blend in.

How many 2x4's were purchased ?

If a 2x4 were really 2" by 4":

If it is 8 feet wide, then since 8*12 = 96, it is 96 inches wide.
If a 2x4 we really 2" by 4", and they were lay flat, the width of each would be 4" and there would be a 0.375" spacing between them.  Since 96/4.375 = 21.94285714,
that would imply we needed 22 rows of 2x4's.

Since the deck is 30' long, and 30/8 = 3.75, we would need 3.75 2x4's for each row.

The total would then be 3.75 x 22 = 82.5, which is really 83 2x4's.

In carpentry, 2x4's, like a lot of other things, are measured before being smoothed out.
Last I knew, the real size of 2x4's is 1.5 * 3.5:

Since they are really 3.5" wide, adding on the 0.375 gives 3.875,
and 96/3.875 = 24.7, which would be 25.
The answer would then be 3.75 x 23.7 = 92.625,
so we would need 93 2x4's.

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Algebra

Volunteer

#### Scott A Wilson

##### Expertise

Any algebraic question you've got. That includes question that are linear, quadratic, exponential, etc.

##### Experience

I have solved story problems, linear equations, parabolic equations. I have also solved some 3rd order equations and equations with multiple variables.

Publications
Documents at Boeing in assistance on the manufacturiing floor.

Education/Credentials
MS at math OSU in mathematics at OSU, 1986. BS at OSU in mathematical sciences (math, statistics, computer science), 1984.

Awards and Honors
Both my BS and MS degrees were given with honors.

Past/Present Clients
Students in a wide variety of areas since the 80's; over 1,000 of them have been in algebra.