64. Back to the bicycle. Let's add a third participant who uses the same bicycle. Suppose Anderson and Brown have brought a person named Carter. They walk at 4.5, 3, and 3 km/h respectively, and ride the bicycle at 10.8, 12, and 12 km/h. How should they use the bicycle so that they all cover the distance of 20 km in the same amount of time?
64. Anderson travels \(7 \frac{11}{27}\), Brown \(1 \frac{13}{27}\), and Carter \(11 \frac{3}{27}\) km, which in total is 20 km. They can travel in any order, but each must use the bicycle only once, and the second rider must walk both before and after the ride. The journey will take each \(3 \frac{8}{9}\) hours, and thus they will all arrive at the destination simultaneously.