A certain combination lock can be set to any sequence of 3 letters 1. How many sequences are possible?

If an Iphone password can have 4 or 6 digit passwords how many combination can there be if there has to be at least one 5

How many ways can we climb a staircase with 8 steps if we can take either 1 or 2 steps at a time? Hint: Group the different ways according to the number of double steps.|

A 100-page document is being printed by four printers. Each page will be printed exactly once. Suppose that the first and the last page of the document must be printed in color, and only two printers are able to print in color. The two color printers can also print black-and-white. How many ways are there for the 100 pages to be assigned to the four printers. Hint: Use the product rule.

How many elements does the power set of {2, 3, 4, 5} have?     Write down four of the elements.

Which of the following situations represents a Combination? Select all that apply. The number of ways you can choose a group of 5 volunteers to paint a house when there are 50 different volunteers to choose from. Creating a password of eight characters using five letters and three numbers. | The number of ways a committee of 3 could be chosen from a group of 20. Picking five students of twelve to ride with you in the van Deciding time slots for three college courses