Answer: 72 ft
Step-by-step explanation:
Given
The width of a post is [tex]w=6\ in.[/tex]
Posts are separated by [tex]5\ ft[/tex] chain
for 2 posts, length is [tex]6+5+6=17\ ft[/tex]
for 3 posts, length is [tex]6+5+6+5+6=28\ ft[/tex]
for 4 posts, it is [tex]28+5+6=39[/tex]
i.e. 11 ft is adding on the addition of another post
for 7 posts it is [tex]17+11\times 5=72\ ft[/tex]
Thus, the total length of the fence is [tex]72\ ft[/tex]
