A model of a dinosaur skeleton was made using a scale of 1 ft : 10 ft in a museum. If the size of the dinosaur's tail in the model is 4 ft, then find its actual length. 1 ft : 10 ft 4 ft : x x = 4ft x 10ft / 1 ft = 40 ft2 / ft = 40 ft ∴ The dinosaur's tail is actually 40 ft long. 8.