4. In a race, there are 15 runners. Trophies for the race are awarded to the runners finishing in first through third place. In how many ways can first through third place
be determined? Show your work.
15!/(15-3)! = 15! / 12! =2730

step-by-step explanation:

no, her answer is not correct.   we square the lengths of all sides and then determine whether the pythagorean theorem holds here:

9² + 15² = 306.   this is not equal to the square of the longest side ( that square being 395.   answer c is correct.