If you flipped a fair coin three times, what is the probability that it would come up "heads" at least once? %

If you flip the coin three times, you have four possible number of heads:

A: No heads. all coins land on tails

B: One heads. one coin lands on heads, two coins land on tails

C: Two heads. two coins land on heads, one coin lands on tails

D: Four heads. all coins land on heads.

You're interested in the union of the latter three events (one, two or all heads). In this case, it is smarter to compute the probability of the remaining event (no heads), and compute the probability of the other three by completing to 1: we have

We have , because we want three consecutive flips to land on tails, and each flip has a probability of 0.5 to land on tails.

So, at least one coin lands on heads with probability

4/6 = 2/3

so it should take 3/3 hours per man. so 9 hours is the answer 3*3 =9

step-by-step explanation:

step-by-step explanation:

we have

using a graphing tool

see the attached figure

this is a quadratic equation (vertical parabola) open up

the vertex is a > vertex

the domain of the function is all real > interval (-∞,∞)

the range of the function is the > [-6.125,∞)

the function has two x->   and

the function is increasing over the > (0.25,∞)

the function is decreasing over the > (-∞,0.25)