Question

A coin is weighted so that it is twice as likely to fall heads as it is tails. If you toss the coin four times, what is the probability of getting four heads is a row?

Answer 1

Let p shows the probability of getting a tail so the probability of getting a head is 2p. Since sum of probabilty must be equal to 1 so

p + 2p = 1

p = 1/3

Therefore the probability of getting a head is 2/ 3

Since each toss is independent from other so the probability of getting four heads is a row, using multiplication rule,  is