Before revision: Since Earth's the angular sizes of the Sun and the Moon, visible from the surface of the Earth, are almost the same, the ratio of the length of the Earth's shadow to the distance between the Earth and the Moon will be almost equal to the ratio of the sizes of the Earth and the Moon.
After revision: Since the angular sizes of the Sun and the Moon, visible from the surface of the Earth, are almost the same, the ratio of the length of the Earth's shadow to the distance between the Earth and the Moon will be almost equal to the ratio of the sizes of the Earth and the Moon.