Lecture on the topic: Combinatorics

Solution : Let's break the solution of the problem into subtasks.

• First, find how many ways you can choose readers:
• we make a choice of 15 people, n=15 ;
• choose 4 people, m=4 ;
• the order is not important, i.e. use the combination rule;
• combinations without repetitions, since different people are chosen.

2. Carrying out similar reasoning, we choose pianists: 3 out of 10 - ways.

2. Carrying out similar reasoning, we choose pianists: 3 out of 10 - ways.

3. Singers: 5 out of 12 - ways.

4. Photographer: 1 out of 20 - ways.

Since the choice is made on all four positions, and not on one, we apply the product rule: .

Answer: you can make a team 2,595 ways.

The founders of combinatorics as a branch of mathematics

Pierre de Fermat
1601 - 1665
Blaise Pascal
1623 - 1662
Thank you for your attention!