Hint for Section 6.4 Question 4b

4. b) Consider the possible dish combinations in three parts:

• you could choose four dishes that do not include either of the pork dishes, or
• you could have the first pork dish and then choose three other dishes excluding the second pork dish, or
• you could have the second pork dish and then choose three other dishes excluding the first pork dish.

Since these three situations cannot overlap, you can then apply the addition rule.

Back to Section 6.4
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