Arace consists of seven runners. how many ways can the runners finish first, second and third?

The way to figure this out is using factorial which is the !. So their are seven runners so it would be 7! (7*6*5*4*3*2*1). However it wants to only know first second and third so it changes things. This then makes it 7*6*5 because you can only have one racer finish in the 3 spots. 

So your answer is 7*6*5=210

Hope this helped!