Algebra question

Question

The Earth revolves around the Sun along an ellipse. The Sun lies in the focus of the ellipse. The largest distance from the Sun to the Earth is 152.1million kilometers, and the shortest is 147.1 million kilometers. Find the length of the semi-minor axis of the ellipse and the eccentricity of the ellipse. What is the distance between the two foci of the ellipse?

Answer 1

The length of the major axis is 152,100,000 + 147,100,000 = 299,200,200 kilometers, so the semi-major axis is 299,200,200/2 = 149,600,000 kilometers

Then, the distance of the focus from the center is 149,600,000 - 147,100,000 = 2,500,000

Thus, the eccentricity is 2,500,000/149,600,000 = .0167

The length of the semi-minor axis is √(149600000² - 2500000²) = 149,579,110 km.

The distance between the two foci is 5,000,000 km. That should have been the first question, as that is the same as the difference between the largest and smallest distance. Alternatively, it is 2,500,00 * 2 = 5,000,000 km.