Respuesta :
The correct answer is:
A) 21
Explanation:
This is a combination of 7 objects taken 5 at a time:
[tex]_nC_r=\frac{n!}{r!(n-r)!}[/tex]
In our case, n = 7 and r = 5:
[tex]_7C_5=\frac{7!}{5!(7-5)!}=\frac{7!}{5!2!} \\ \\=\frac{7\times 6\times 5\times 4\times 3\times 2\times 1}{5\times 4\times 3\times 2\times 1\times 2\times 1} \\ \\=\frac{5040}{240} = 21[/tex]
A) 21
Explanation:
This is a combination of 7 objects taken 5 at a time:
[tex]_nC_r=\frac{n!}{r!(n-r)!}[/tex]
In our case, n = 7 and r = 5:
[tex]_7C_5=\frac{7!}{5!(7-5)!}=\frac{7!}{5!2!} \\ \\=\frac{7\times 6\times 5\times 4\times 3\times 2\times 1}{5\times 4\times 3\times 2\times 1\times 2\times 1} \\ \\=\frac{5040}{240} = 21[/tex]