Math Help Forum: Combinations

Naomi invites 8 friends over to a party on short notice, so they may not all be able to come. how many combinations of guests could there be?

no idea how to do this

Hello, Jason2JZ!

Naomi invites 8 friends over to a party on short notice,
so they may not all be able to come.
How many combinations of guests could there be?

For each of the 8 friends, there are two choices: come to the party, or not.

The number of possible combination is: .

This includes every possible outcome: from "no one comes" to "everyone comes".
.

OHH righttt. so for every person invited there are 2 possible outcomes of whether or not they show up. ahh ic thank you ill have plenty more questions tonight lol. i have another one comming up actually :S