There are two different ways in which he can choose 9 sandwitches. It can be solve by the concept of permutation and combination.
What is permutation and combination?
A permutation is an arrangement of several items taken one at a time or all at once in a specific order.
Combinations are based entirely on grouping. Combinations can be used to determine how many different groups that can be created from the available items.
Since all vegitarian sandwiches looks like same and all sandwitches with meat looks like same hence, their order will not affect the number of choice.
If 8 sandwitches are vegitarian then 1 sandwitch must be with meat. So that total sandwithches becomes 9.
If all 9 sindwitches are vegetarian then there is no option to choose another sandwitch. Because he can choose only 9 sandwitches.
Hence, there are two different ways in which he can choose 9 sandwitches.
Learn more about permutation and combination from the following link:
https://brainly.com/question/3901018#:~:text=Expert%2DVerified%20Answer&text=If%20the%20order%20of%20the,n%2Dr)!
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