Thanks for the reply, but your method leaves duplicate choices. This question came from an state-sponsored math exam and the correct response is 495. I just need to find the formula for future reference.
Thanks for the reply, but your method leaves duplicate choices. This question came from an state-sponsored math exam and the correct response is 495. I just need to find the formula for future reference.
The question is vague. But the given answer implies a multi-set.
The number of ways to put K identical units into N different cells is $\displaystyle \binom{K+N-1}{K}$.
Here the choices are identical and the pizzas are different.
$\displaystyle \binom{4+9-1}{4}=495$
Thank You, Plato. That is the formula I was looking for. I had seen it a few months ago, but had forgotten. Thanks for reminding me. I will write it down this time. Fholik