Question

a coin is tossed 6 times . find the probability of obtaining no head

Answer 1

Total possible outcomes(denominator) :- 2 possibilities for each toss, six tosses, so 2^6 = 64. That's the denominator.

For the numerator (favorable outcomes), for this case, obviously you can't have two heads in a row. There's only one way this can happen: TTTTTT
Therefore answer is 1/64.