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. 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?
Here are some hints from Geno,
https://web2.0calc.com/questions/hints-only-please