Question

A straight fence is constructed from posts 6 inches wide and separated by lengths of chain 5 feet long. A certain fence begins and ends with a post. If there are 7 posts, what is the total length of the fence?

Answer 1

Answer: 72 ft

Explanation:

Given

The width of a post is
`w=6\ in.`

Posts are separated by
`5\ ft` chain

for 2 posts, length is
`6+5+6=17\ ft`

for 3 posts, length is
`6+5+6+5+6=28\ ft`

for 4 posts, it is
`28+5+6=39`

i.e. 11 ft is adding on the addition of another post

for 7 posts it is
`17+11* 5=72\ ft`

Thus, the total length of the fence is
`72\ ft`