terrydavis1206
39

# I have some idea about how to solve this but I am not sure So please show your work

nPr=$\frac{n!}{(n-r)!}$ 9P3=$\frac{9!}{(9-3)!}$= 9!/6!=(9*8*7*6*5*4*3*2*1)/(6*5*4*3*2*1) cancel= (9*8*7)/(1)=504 ways nCr=$\frac{n!}{r!(n-r)!}$ 10C4=$\frac{10!}{4!(10-4)!}$= $\frac{10!}{4!(6)!}$= $\frac{10*9*8*7*6*5*4*3*2*1}{4*3*2*1*6*5*4*3*2*1}$, cancel= $\frac{10*9*8*7}{4*3*2*1}$= $\frac{2*5*3*3*2*4*7}{4*3*2*1}$= $\frac{5*3*2*7}{1}$=210