Pat starts with two identical square pieces of paper. On the first one, she draws straight lines that divide the paper into a 3-by-3 grid of squares. The total length of the lines she draws is 18 cm.
On the second piece of paper, Pat draws straight lines that divide the paper into a 6-by-6 grid of squares.
What is the total length of the lines that Pat draws on the second piece of paper?
Since the large square has four times the area of the small square, the total length of the lines in the large square is 4*18 = 72.
I am disappointed to see that you have reposted this without referencing this original post.
If you repost you must give the address of the original and request that people answer on the original thread.
Also, if you believe an answer is wrong please give your reason. (Even if It is just 'I put it in the answer box and was told it was wrong')