From a squad of 12 cheerleaders, 10 will assemble themselves into a 4-level pyramid at the Homecoming rally.
1.) How many different combinations of cheerleaders can be used to build the pyramid?
For this I got 12C10=66......Right or Wrong?
2.) The coach decides that Alexis must be at the top of the pyramid, and that Rachel, Jennifer, Brittany, and Nicole will form the base of the pyramid. How many different combinations of 10 cheerleaders can now be chosen to form the pyramid?
For this I got 7C5=21....Right or Wrong?
3.) Suppose Alexis has an injury and is unable to participate. The coach replaces Alexis with Rebecca. Now how many different combinations of 10 cheerleaders can the coach select?
I got 6C5=6........Right or Wrong?
1 answer