Lesson: Finding Probability Using Permutations

A small combination padlock can be opened by entering three different specified numbers from 1 to 9 in a specified order. Benjamin has 10 attempts to guess the combination. Determine the probability of him opening the lock.

Two people are chosen randomly from a group of six hundred two. What is the probability that Benjamin was selected first and Ethan second?

David and Amelia are graduating in a class of 57 students. If each student is assigned a number from 1 to 57 at random, what is the probability that David’s number will be 1 and Amelia’s will be 2?