A fence consist of sections built in a row. the figure above shows the first two sections of the fence. each section is identical and consists of two horizontal boards between consecutive vertical posts. each post cost $ 8 and each board coat $6. If the total cost of the boards and post was $ 208. how many post are in the fence?
The thing you have to recognize is that there is a post at the zero position—if there are n sections of fence, there are n + 1 posts. (You can see this in the figure shown, I’m sure. There are two sections of fence, but three posts.
So, set up an equation to solve. There’s the first post, which costs $8. Then each section adds $8 for a post and a total of $12 for the two boards. So if there are n sections, we can solve for n thusly:
208 = n(12 + 8) + 8
200 = 20n
10 = n
So there are 10 sections of fence, which means there are 11 posts.