Question

How many combinations are possible? Assume that the items are distinct. Please show work. 12 items chosen 7 at a time

Answer 1

792

Explanation:

`\binom{12}{7}=(12!)/(7!5!) \\ \\ =(12 \cdot 11 \cdot 10 \cdot 9 \cdot 8 \cdot 7!)/(7!5!) \\ \\ =(12 \cdot 11 \cdot 10 \cdot 9 \cdot 8)/(120) \\ \\ =11 \cdot 9 \cdot 8 \\ \\ =792`