Fence posts stand in a single straight line, 5 m apart. A painted post is 8th from the left end and 18th from the right end of the line. How far is the painted post from the post that stands exactly at the centre of the line?
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → 25 m
Find the number of posts from the two-end count, locate the centre post, and count the gaps between the two posts.
Posts in the line \(=8+18-1=25\)
With 25 posts, the centre post has 12 posts on each side: it is \(12+1=13\)th from the left
Gaps between the 8th and the 13th post \(=13-8=5\)
Distance \(=5\times5=25\,\mathrm{m}\)
