Question

A coin is to be tossed until a head appears twice in a row. What is the sample space for this experiment? If the coin is fair, what is the probability that it will be tossed exactly four times?

Answer 1

Answer:

The sample space would be infinite

{HH, TTTHH, TTTTHH, TTTTTTTHH.......................}

1/8

Step-by-step explanation:

The sample space would be infinite

{HH, TTTHH, TTTTHH, TTTTTTTHH.......................}.

This is because the number of times the coin would be flipped is not specified. So, you can keep flipping the coin forever.

If the coin is tossed four times then the sample space would be

{HHHH HTHH THHH HTHT

HHHT HTTH TTHH THTH

HHTT HHTH TTTH THHT

HTTT TTTT TTHT THTT}

HTHH and TTHH are the only two cases where two consecutive tosses will result in two heads

Probability that the coin will be tossed four times is 2/16 = 1/8