seven numbers of the board of management of a had their meeting on a Saturday morning. on entering the board room they greeted each other by shaking hands. everyone shook hands with every other members. in other words, all of them shook hands with one another once. how many handshakes took place in the room?

Respuesta :

Answer:

there were a total of 21 handshakes that took place in the room.

Step-by-step explanation:

To find the total number of handshakes that took place in the room, we can use the combination formula.

Given that there are 7 members on the board of management, and each member shakes hands with every other member, we need to find the total number of combinations of 2 members out of 7. This will give us the total number of handshakes.

The combination formula is given by:

\[ C(n, k) = \frac{n!}{k!(n-k)!} \]

Where:

- \( n \) is the total number of items (in this case, the total number of members),

- \( k \) is the number of items to choose (in this case, 2 members for a handshake),

- \( n! \) denotes the factorial of \( n \), which is the product of all positive integers up to \( n \).

Substituting the values into the formula:

\[ C(7, 2) = \frac{7!}{2!(7-2)!} \]

\[ C(7, 2) = \frac{7!}{2!5!} \]

\[ C(7, 2) = \frac{7 \times 6}{2 \times 1} \]

\[ C(7, 2) = \frac{42}{2} \]

\[ C(7, 2) = 21 \]

So, there were a total of 21 handshakes that took place in the room.