Answer:
0.0078125
Step-by-step explanation:
Probability of tail, p = 0. 5
Probability of getting all tails from 7 tosses :
P(tail) * P(tail) * P(tail) * P(tail) * P(tail) * P(tail) * P(tail)
0.5 * 0.5 * 0.5 * 0.5 * 0.5 * 0.5 * 0.5 = 0.0078125
We could also use the binomial probability formula :
P(x =x) = nCx * p^x * (1 - p)^(n - r)
n = 7 ; x = 7, p = 0.5,
P(x = 7) = 7C7 * 0.5^7 * 0.5^0 = 0.0078125
