Question 1166487
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A chair is being re-upholstered. The back is a square, 27" x 27". Tacks used are 7/16" diameter (tack head). 
Tacks are placed uniformly, 1/4", around the square. Determine number of tacks used.
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        I read this problem and also read the solution by @CPhill (= artificial intelligence),
        and I did not get, why so many words are there.


        My reasoning/solution will be much shorter.



<pre>
The diameters of the tacks is  7/16''  - - - hence, the radius is  7/32''.


The distance between the tacks is  1/4''  or  8/32'',  so the tacks heads do not interfere 
with the placement of tacks.


In each side of 27'' long, there are  {{{27/((1/4))}}} = 108 gaps between tacks.


So, in each side,  we have 108 tacks, and the total tacks is 4*108 = 432.


<U>ANSWER</U>.  432 tacks.
</pre>

Solved.