Question

Event Not Occurring. Determine the probability of the following events. State anyassumptions that you use.What is the probability of not tossing 3 heads with three fair coins?

Answer 1

Step 1

Write the sample space.

`ttt,tht,tth,htt,hhh,hth,hht,thh`

Therefore, the probability of getting 3 heads(hhh) is given as

`\begin{gathered} \text{Probability}=\frac{number\text{ of required outcome}}{\text{Total number of outcomes}} \\ \text{Number of required outcomes = 1} \\ \text{Total number of outcomes = 8} \\ \text{The probability of tos}\sin g\text{ 3 heads(hhh)=}(1)/(8) \end{gathered}`

Step 2

Find the probability of not tossing 3 heads with three fair coins is given as;

`\begin{gathered} Pr(\text{not tossing 3 heads) = 1-pr(tossing 3 heads(hhh))} \\ Pr(\text{not tossing 3 heads) }=1-(1)/(8)=(7)/(8) \end{gathered}`

Hence, the probability of not tossing 3 heads with three fair coins = 7/8