Five Elements, Three From the Front
Difficulty: Medium · Topics: Discrete Mathematics, Sets, Subsets
A=\1,2,3,4,5,6,7,8\ and Bsubseteq A, and the set Bcap\1,2,3,4\ has 3 elements.
How many different five-element sets B can be written?
Difficulty: Medium · Topics: Discrete Mathematics, Sets, Subsets
A=\1,2,3,4,5,6,7,8\ and Bsubseteq A, and the set Bcap\1,2,3,4\ has 3 elements.
How many different five-element sets B can be written?