Hello! My name is Christie. I am in middle school and I'm a student. I have some questions that I was stuck on and I was hopting if you could help me on those questions. In order to promote the 2000 Census and encourage participation, 12 Road Tour Vehicles(RTV's) set out from 12 locations across the US for a 10 week promotion tour last February. The RTV's reportedly traveled a total combined distance of 97,911 miles. What was the aberage number of miles traveled in a day by each RTV? 2. The 12 RTV's mentioned above traveled a total combined distance equivalent to traveling 12.35 times around the earth at the equator. To the closest mile, what is the radius of the earth? Use 3.14 as your approximation for pi. Hi Christie, Your questions sound really interesting, here's how I would start them: Finding the "average number of miles travelled in one day by each RTV" will require that you find two averages. First you have to take the total miles travelled by all 10 of them together and then divide by how many RTV's there were (which is 10) to get the average total miles travelled by each RTV over the 10 weeks. Next you need to determine how many days each RTV travelled. Well, 10 weeks is 10 x 7 = 70 days. Now to find the average number of miles travelled in one day by each RTV, you must divide the average total miles travelled by each RTV by the number of days travelled. We know that the formula for the circumference of circle (which is what the equator is) is Circumference = pi * 2 * radius. Travelling around the equator once will give you the earth's circumference so if we know 97,911 miles is 12.35 times the circumference, then to find the value for the circumference, divide the total distance travelled by the RTV's by 12.35. Now to find the radius, we must divide the circumference by 2*pi or 2 * 3.14 = 6.28. Hope this helps, Leeanne Go to Math Central