contestada

8 junior high classes will be chosen to participate in a school improvement survey. There are 21 junior high classes in the school. In how many ways can the classes be chosen?

Respuesta :

Answer

The classes can be chosen in 203,490 ways

Step-by-step explanation

The number of combinations of n things chosen r at a time is found using the next formula:

[tex]nCr=\frac{n!}{r!(n-r)!}[/tex]

In this case, we have to choose r = 8 junior high classes from a total of n = 21 classes. Substituting these values into the formula, we get:

[tex]\begin{gathered} _{21}C_8=\frac{21!}{8!(21-8)!} \\ _{21}C_8=203,490 \end{gathered}[/tex]

Otras preguntas