Permutation question pictured! Thanks :)

Mathematics

1 answer:

lozanna [386]3 years ago

6 0

Answer:

3,160,080

Step-by-step explanation:

The first place can be taken by any one of the 22 students.
The second place can be taken by any one of the remaining 21 students.
The third place can be taken by any one of the remaining 20 students.
The fourth place can be taken by any one of the remaining 19 students.
The fifth place can be taken by any one of the remaining 18 students.

<em>This basically means multiplying 22, 21, 20, 19, and 18. Or, the number of permutation of 22 things taken 5 at a time.</em>

The answer is 22*21*20*19*18 = 3,160,080

<em>Using formula $nPr=\frac{n!}{(n-r)!}=\frac{22!}{(22-5)!}=\frac{22!}{17!}=(22*21*20*19*18)=3,160,080$ </em>

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