Practice Permutation in Math

Use these practice problems to test your method after reviewing the concept explanation and worked examples.

Quick Recap

A permutation is an ordered arrangement of objects — the number of ways to choose and order r items from n distinct items is P(n,r)=n!(n−r)!.

With permutations, order matters — first place and second place are different. Think of ranking students: ABC and BAC are different orderings.

Showing a random 20 of 50 problems.

Example 1

hard
In how many ways can 5 different books be arranged on a shelf if 2 specific books must always stand together?

Example 2

medium
Compute P(6,3)P(6,2).

Example 3

easy
How many ways can 3 distinct books be arranged on a shelf?

Example 4

hard
A license plate has 3 letters (no repeats, from 26) followed by 3 digits (no repeats, from 0–9). How many such plates exist?

Example 5

challenge
How many ways can 8 different beads be arranged on a circular bracelet, treating rotations AND reflections as the same?

Example 6

easy
Does P(n,r)=nr in general?

Example 7

challenge
In how many ways can the letters of ARRANGE be arranged so that the two R's are NOT adjacent?

Example 8

easy
Compute P(3,3).

Example 9

easy
Compute P(8,3).

Example 10

medium
How many 3-digit numbers (no repeated digits) can be formed from 1,2,3,4,5?

Example 11

medium
Solve for n: P(n,3)=120.

Example 12

medium
How many 5-letter words (real or nonsense) can be formed from {A,B,C,D,E,F,G} with no repeats?

Example 13

medium
A club of 8 students must choose a president, vice president, and secretary. In how many ways can the officers be chosen?

Example 14

easy
Compute P(6,1).

Example 15

hard
How many ways can 7 people sit in a row if two specific people refuse to sit next to each other?

Example 16

easy
True or false: P(n,n)=n!.

Example 17

easy
How many 2-letter ordered codes (no repeats) use letters from {A,B,C,D,E}?

Example 18

medium
How many ways can the letters of LEVEL be arranged?

Example 19

easy
In how many ways can 3 medals (gold, silver, bronze) be awarded to 6 runners?

Example 20

easy
Compute P(5,2).