Question

Find the number of permutations of the first 10 letters of the alphabet, taking 3 letters at a time.

Answer 1

Answer:

720

Step-by-step explanation:

The permutation looks like this for that set of data:

$_{10}P_{3}$

and the formula to solve it like this:

$_{10}P_{3} =\frac{10!}{(10-3)!}$

which simplifies down to

$_{10}P_{3} =\frac{10!}{7!}$

Since every number less than 8 in the numerator cancels out with the denominator, we have

$_{10}P_{3}=10*9*8$

which equals 720