Question: FACTORIAL. COMBINATIONS. PERMUTATIONS. N! CrN= N! / r!(N -r)! PrN= N! / (N -r)! A) A security system uses a 3-letter password, but no letter

FACTORIAL. COMBINATIONS. PERMUTATIONS.

N!

CrN= N! / r!(N -r)!

PrN= N! / (N -r)!

A) A security system uses a 3-letter password, but no letter can be used more than once. How many possible passwords are there if 12 of the letters of the alphabet can be used by the system? The N represents the total number of possible objects being counted

For this question indicate only what the value of N is?

B) A security system uses a 2-letter password, but no letter can be used more than once. How many possible passwords are there if 21 of the letters of the alphabet can be used by the system? The r represents the number of objects that are being selected.

For this question indicate only what the value of r is?

C) A security system uses a four-letter password, but no letter can be used more than once. How many possible passwords are there if 25 of the letters of the alphabet can be used by the system?

Step by Step Solution

There are 3 Steps involved in it

1 Expert Approved Answer
Step: 1 Unlock blur-text-image
Question Has Been Solved by an Expert!

Get step-by-step solutions from verified subject matter experts

Step: 2 Unlock
Step: 3 Unlock

Students Have Also Explored These Related Mathematics Questions!