Question 1182910
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Bob is building a deck that is 25 feet long, and he has posts that are 6 inches square 
to use to build the railing. If he puts the posts 3 feet apart with one on each end, 
how many posts will he use?
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            A TWIN problem was solved at this forum long time ago by tutor @josmiceli under this link


            https://www.algebra.com/algebra/homework/word/misc/Miscellaneous_Word_Problems.faq.question.802321.html


            So, I copied that solution and changed the numbers in it, respectively.

            Below is the updated solution.




There is going to be 1 more post than the number of 
spaces between posts. For example, if there were 10 
spaces, there would be 11 posts
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Let {{{ n }}} = the number of {{{ 3 }}} ft spaces
{{{ n + 1 }}} = the number of posts
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Note that {{{ 6 }}} in = {{{ .5 }}} ft
{{{ 3n + .5*( n + 1 ) = 25 }}}
{{{ 3n + .5n + .5 = 25 }}}
{{{ 3.5n = 24.5 }}}
{{{ n = 7 }}}
{{{ n+ 1 = 8 }}}
He will use 8 posts.     &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<U>ANSWER</U>
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check:
{{{ 3n + .5*( n + 1 ) = 25 }}}
{{{ 3*7 + .5*8 = 25 }}}
{{{ 21 + 4 = 25 }}}
{{{ 25 = 25 }}}
OK