Answer:
720 ways.
Explanation:
Given:
A catering service offers 10 appetizers, 4 main courses, and 6 desserts.
A costumer is to select 9 appetizers, 2 main courses, and 5 desserts for a banquet.
Question asked:
In how many ways can this be done ?
Solution:
By applying combination's formula:-

A costumer can choose 9 appetizers out of 10 in =

A costumer can choose 2 main courses out of 4 in =

A costumer can choose 5 desserts out of 6 in =

Total number of ways =

Therefore, A costumer can select 9 appetizers, 2 main courses, and 5 desserts for a banquet in 720 ways.