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Hi, can you help me answer this question, please, thank you:)

Hi, can you help me answer this question, please, thank you:)-example-1
User Khaled Osman
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1 Answer

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The question requires that we use the binomial probability distribution

To do this, we will use the binomial formula


^nC_r* P^r* q^(n-r)

Where


\begin{gathered} P=\text{ probability of success} \\ q=\text{ probabilty of failure} \\ n=\text{ number of times} \\ \end{gathered}

In our case


P=76\text{ \%=}(76)/(100)=0.76
\begin{gathered} q=1-p=1-0.76=0.24 \\ q=0.24 \end{gathered}


n=12

For the first question,

We are told to find the probability that exactly 6 jurors are Asian American

In this case,


\begin{gathered} r=6 \\ \end{gathered}

So applying the formula


\begin{gathered} (P=6)=>^(12)C_6*0.76^6*0.24^(12-6)=^(12)C_6*0.76^6*0.24^6 \\ \\ (P=6)\Rightarrow924*0.1927*1.911*10^(-4)=0.0340 \\ \\ \end{gathered}

Thus, the probability that exactly 6 jurors are Asian American =0.0340

For the second question

We are told to find the probability of 6 or fewer than 6 are Asian Americans


\begin{gathered} \text{When r=0} \\ (P=0)\Rightarrow^(12)C_0*0.76^0*0.24^(12)=^(12)C_0*0.76^0*0.24^(12) \\ (P=0)=1*1*3.65^{}*10^(-8) \\ P\text{ is appro}\xi mately\text{ 0} \end{gathered}

We will repeat this for when r=1, 2, 3, 4, 5 and 6

And then we will sum the values up


\begin{gathered} \text{When r=1} \\ P=\text{appro}\xi\text{mately 0} \end{gathered}


\begin{gathered} when\text{ r=2} \\ P\approx0.0002 \end{gathered}


\begin{gathered} \text{when r=3} \\ P\approx0.00026 \end{gathered}
\begin{gathered} \text{when r=4} \\ P\approx0.00182 \end{gathered}


\begin{gathered} \text{when r=5} \\ P=0.00921 \end{gathered}


\begin{gathered} \text{when r=6} \\ P=0.03403 \end{gathered}

Then

The probability of 6 or fewer than 6 are Asian Americans = P(0)+P(1)+P(2)+P(3)+P(4)+P(5)+P(6)

Thus,

The probability of 6 or fewer than 6 are Asian Americans = 0+0+0.00002+0.00026+0.00182+0.00921+0.03403=0.04534

The probability of 6 or fewer than 6 is Asian Americans=0.04534

For the third part

The probability of more than 10 will be

The sum of the probabilities when r = 11 and r =12


\begin{gathered} \text{when r=11} \\ ^(12)C_(11)*0.76^(11)*0.24^(12-11)=^(12)C_(11)*0.76^(11)*0.24^1=0.14072 \end{gathered}


\begin{gathered} \text{when r=12} \\ ^(12)C_(12)*0.76^(12)*0.24^(12-12)=^(12)C_(12)*0.76^(12)*0.24^0=0.03713 \end{gathered}

Thus, the total probability = P(11) + P(12)= 0.14072 +0.03713 = 0.17785

Hence,

The probability of more than 10 Asian-Americans will be = 0.17785

User Keyshia
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