You want to then multiply 5*4*3 to represent the different combinations we can make for each place. This gives us a total of 60 different possible ways that the runners can come in 1st, 2nd, and 3rd place, assuming no ties.
The length of the side of the small triangle is 4...the side length of the large triangle is 9 (5+4), not 5. It should be correctly written as 4/6 = 9/x
