A certain panel is to be composed of exactly three women and exactly two men, chosen from x women and y men. How many different panels can be formed with these constraints? This is a data sufficiency question, and I understand that with certain information, this problem can be solved. If you did hav...

thank you for your help!

*this is from a gmat flashcard Sn = Sn-1 - 10 and S3 = 0 I calculated the answer the long way. This was easy, since this was only the 25th term. But I don't understand how the equation to solve this is derived, and I want to understand it in case the test asks for the 500th term. The explanation not...

What I don't understand is that if the group has moved an additional 120 feet in 40 seconds, would it not take Bill 80 seconds to catch up to them at the 240 foot mark? 40 seconds for the first 120 feet and 40 seconds for the next 120 feet.