Question

If a fair coin is flipped three times, the probability it will land heads up all three times is 1/8. Which of the following is the probability that when a coin is flipped three times at least one tail will show up?

(1) 7/8
(2) 1/8
(3) 3/2
(4) 1/2​

Answer 1

1. 7/8.

Explanation:

There are a total of 8 possible outcomes (2*2*2) when you toss a coin 3 times.

The only outcome when there is no tail shown is HHH.

So the answer is 1. 7/8.

Answer 2

7/8

Explanation:

if the probobilty that all three will be heads is 1/8 the probobilty of tails showing up once is 7/8 because 8/8 - 1/8= 7/8