Question

Gerri flips a coin three times. With each flip, she records the outcome as heads (H) or tails (T). Which of the following lists shows all of the possible outcomes where Gerri records at least one tail?
A. THH, HTH, HHT, TTH, THT, HTT, TTT
B. THH, TTH, TTT
C. THH, HTH, HHT, HHH, TTH, THT, HTT, TTT
D. THH, HTH, HHT, TTT

Answer 1

The first flip can be heads or tails: 2 possibilities
The second flip can be heads or tails: 2 possibilities
The third flip can be heads or tails: 2 possibilities

Total possibilities: 2 x 2 x 2 = 8

So there should be 8 total possibilities.

Answer 2

There'll be 7 total possibilities where she gets at least one tail - HHH is the only way to not get a tail.

Answer 3

Yes @agent0smith. I did not read the full question!
Thought they just wanted a list of all possible outcomes.