A coin is thrown 3 times .what is the probability that atleast one head is obtained?
Simply exclude the prob of all tails
Prob(all tails) = (1/2)^3 = 1/8
So prob(at least 1 head) = 1 - 1/8 = 7/8
To calculate the probability of getting at least one head when throwing a coin three times, we need to find the probability of the complementary event (the event of not getting any heads) and subtract it from 1.
To calculate the probability of not getting any heads when throwing a coin, we need to calculate the probability of getting tails on all three throws. Since each throw is an independent event with two possible outcomes (heads or tails), the probability of getting tails on one throw is 1/2. Therefore, the probability of not getting any heads on three throws is (1/2) * (1/2) * (1/2) = 1/8.
Now, to find the probability of getting at least one head, we subtract the probability of not getting any heads from 1:
Probability of at least one head = 1 - Probability of not getting any heads
= 1 - 1/8
= 7/8
Therefore, the probability of obtaining at least one head when throwing a coin three times is 7/8.