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

Step-by-step 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 $17+11\times 5=72\ ft$

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