Probability
# Distribution into Bins

Once Calvin and his friends were very hungry and they decided to go to the McDonalds to satisfy their craving.

In the McD menu, there were 4 burgers mentioned: McVeggie, McChicken, Chicken Maharaja - Mac, and Filet-o-Fish.

If Calvin ordered 10 burgers in total, in how many ways can Calvin buy the burgers? Note that the order does not matter.

How many three digit numbers are there such that the sum of the digits in each number is 10.