We drew the diagrams above in the tiny town or Terlingua, Texas during breakfast on the 10th day of an assignment I photographed for Field and Stream a few years back. We were on a trip following, floating, and fishing the entire length of the Rio Grande River from source to sea. The diagrams (if you can call them that) were helping us figure out how to float a very remote canyon on the southeast corner of Big Bend National Park. The problem: What's the most efficient way to shuttle three guys, one canoe, and a one-man raft across a 30-mile stretch of wilderness desert two-track using two motorcycles and a Toyota 4Runner? We went through about six or seven iterations in our head and on paper before we finally figured it out. If I remember correctly it took about 30 minutes to do so. Math problems get harder when you're ten days on the road.