1. The problem statement, all variables and given/known data Hello. Me and my partner are in Grade 7, and are currently doing an inquiry project in Math. We were told to take a question, and calculate theoretical probability of both outcomes. In this case, it would be surviving or dying. Our question is: What is the probability of surviving if the moon struck Earth at 3,683km/h? We had a lot of smaller questions that were easily answered, and 4 days from the due date, we get stuck on this. Since we're using the moon, and the Earth, we have this data: Surface area of Earth: 510,072,000 km² Surface area of the Moon: 37,930,000 km² 2. Relevant equations We googled "contact area between to spheres", and Wikipedia had a formula: But we have no way of telling if the formula is correct. Also, the variables aren't defined anywhere in the entry. 3. The attempt at a solution Honestly, we couldn't even get here. The first thing we tried was diving the Earth's surface area by the moon's, but than we realized that not all of the moon will be touching the Earth, and that's where contact mechanics come in. Can anyone help?