9. In a room, there are 8 chairs in a row. In how
many ways can 6 students be seated in
consecutive chairs?
A. 2
B.720
C. 20 160
D. 21 060​


Sagot :

[tex] \large\underline \mathcal{{QUESTION:}}[/tex]

9. In a room, there are 8 chairs in a row. In how many ways can 6 students be seated in consecutive chairs?

  • A. 2
  • B. 720
  • C. 20 160
  • D. 21 060

[tex]\\[/tex]

[tex] \large\underline \mathcal{{SOLUTION:}}[/tex]

Using the linear permutation

  • Given that n=8 and r=6

[tex]\\[/tex]

[tex]\sf{P(n,r)=\frac{n!}{(n-r)!}}[/tex]

[tex]\sf{P(8,6)=\frac{8!}{(8-6)!}}[/tex]

[tex]\sf{P(8,6)=\frac{8!}{2!}}[/tex]

[tex]\sf{P(8,6)=\frac{8 \times 7 \times 6 \times 5 \times 4 \times 3 \times 2 \times 1}{2 \times 1}}[/tex]

[tex]\sf{P(8,6)=\frac{8 \times 7 \times 6 \times 5 \times 4 \times 3 \times \cancel{2 \times 1}}{ \cancel{2 \times 1}}}[/tex]

[tex]\sf{P(8,6)=8 \times 7 \times 6 \times 5 \times 4 \times 3 } [/tex]

[tex]\sf{P(8,6)=20,160}[/tex]

[tex]\\[/tex]

[tex] \large\underline \mathcal{{ANSWER:}}[/tex]

  • OPTION C (20,160)

[tex]\\[/tex]

[tex]\\[/tex]

To learn more about problems involving permutations: Visit this link

https://brainly.ph/question/13885772