2 years ago

In how many ways can 4 books be arranged on a shelf if there are 8 books to choose from?

Mathematics

1 answer:

dsp732 years ago

8 0

Answer:

1680 ways

Step-by-step explanation:

By using the formula for permutation, which is nPr=n!/(n-r)!,

8P4=8!/(8-4)!

=8!/4!

=8×7×6×5

=1680

Or if you just want to use the multiplication rule (which is simpler).

8×7×6×5=1680

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