Count in binary.

[Princess Mint]

If you don't know how to count in binary, think of it as creating the next largest number that you're able to come up with using only 0s and 1s.

0.

 

[TheBlueCatMenace]

1

 

[Marceline]

10

 

[TheBlueCatMenace]

11

 

[Princess Mint]

100

 

[Marceline]

101

 

[TheBlueCatMenace]

111

 

[Marceline]

111

That should be 110. 101 = 5, 110 = 6, 111 = 7.

111.

 

[Zdrmonster Productions]

1000

 

[Princess Mint]

1001

 

[Nellie Rose Morningstar]

1010

 

[Zdrmonster Productions]

1011

 

[Princess Mint]

1100