How many three-symbol codes can be formed from the

letters I, S, P, and Y without repetition?

What is 4*3*2?

Can you please show me how you got that answer?

How many three-symbol codes (letter-number-number)

can be made from the letters S, P, Y, and two digits
from the set {0, 1, 2,....., 9} without repetition?

As far as your first question, I think bobpursley is referring to 4! called "four factorial."

To determine the number of three-symbol codes that can be formed from the letters I, S, P, and Y without repetition, we can use the concept of permutations.

A permutation is an arrangement of objects in a specific order. In this case, we want to find the number of permutations of three letters taken from a set of four letters (I, S, P, and Y).

To calculate the number of permutations, we can use the formula for permutations of n objects taken r at a time, which is given by:

P(n, r) = n! / (n-r)!

In this case, we want to find the number of permutations of three objects (r = 3) taken from a set of four objects (n = 4).

Using the formula, we can calculate the number of permutations:

P(4, 3) = 4! / (4-3)!
= 4! / 1!
= 4 x 3 x 2 x 1 / 1
= 24 / 1
= 24

Therefore, there are 24 different three-symbol codes that can be formed from the letters I, S, P, and Y without repetition.