A fair coin is tossed seven times. what is the probability of getting at least one tail?
127/128 this is right
To calculate the probability of getting at least one tail when a fair coin is tossed seven times, you need to calculate the probability of not getting any tails and then subtract it from 1.
The probability of getting a tail on a single coin toss is 1/2 (since a fair coin has two equally likely sides - heads and tails).
To find the probability of not getting any tails on a single coin toss, you need to find the probability of getting a head on each toss.
So, the probability of not getting a tail on a single toss is also 1/2.
Since each toss is independent, you can multiply the probabilities together to find the probability of not getting any tails on all seven tosses:
(1/2) * (1/2) * (1/2) * (1/2) * (1/2) * (1/2) * (1/2) = (1/2)^7
Now, to find the probability of getting at least one tail, you subtract the probability of not getting any tails from 1:
1 - (1/2)^7 = 1 - 1/128 = 127/128.
Therefore, the probability of getting at least one tail when a fair coin is tossed seven times is 127/128.
That would the probability of 1 - probability of no tails.
1 - .5^7 = ?