Matt goes to the fastener aisle in the hardware store which has wood screws, sheet metal screws, hex bolts, carriage bolts and lag bolts. How many ways can he choose 10 fasteners if he needs at least one of each kind?

Respuesta :

Matt has 5 different screws and he will choose 10, so the total combinations are:

[tex](\begin{aligned}10 \\ 5\end{aligned})=\frac{10!}{(10-5)!5!}=\frac{10\cdot9\cdot8\cdot7\cdot6}{5!}=\frac{30240}{120}=252[/tex]

There are 252 different ways.