After one of them is chosen for 1st, there are only 9 choices for 2nd, and then there are only 8 choices for 3rd... and so on. There are 720 different ways to pick 1st, 2nd, and 3rd place from among 10 original students
165^2 + 220^2 = X^2
27225 + 48400 = 75625
sqrt(75625) = 275
answer is A 275 yards
