Understanding Addition Principle

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Given from a ala-carte food Menu to choose for

Starter Course = 3 items

Main Course = 6 items

Desert course =3 items (cheesecake or fruit tarts or ice-cream)

Question: Find the number of meal that satisfies the following condition:

One Starter course, one main course and "an optional dessert course"

Can i know what does "an optional" in the question refer to? Thank you.

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Just to give this a more mathematical foundation we will use the property of counting independent items.

Just like Rohan said the answer is 72. If you wanted to be able to find the answer to another similar problem just notice you are choosing 1 starter course (from 3 options), 1 main course (from 6 options), 1 desert course (from 4 options). This is, $$\binom{3}{1}\binom{6}{1}\binom{4}{1} = \frac{3!}{1!2!}\frac{6!}{1!5!}\frac{4!}{1!3!} = 3*6*4 = 72$$