Question

Answer the following:

Find the number of ways of dividing 20 objects in three groups of sizes 8, 7 and 5

Answer 1

Required number = ²⁰C₈ × ¹²C₇ × ⁵C₅

= `(20!)/(8!12!) xx (12!)/(7!5!) xx1`

= `(20!)/(8!7!5!)`