Question 1192115
.
After studying Mr X's family history, a doctor determines that the probability of any child 
born to this couple having a gene for disease X is 1 out of 4. If Mr X has three children, 
what is the probability that exactly two of the children have the gene for disease X?
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Standard binomial distribution problem.


<pre>
    P = {{{C[3]^2*(1/4)^2*(1-1/4)^1}}} = {{{3*(1/4)^2*(3/4)}}} = 0.1406  (rounded).    <U>ANSWER</U>
</pre>

Solved.


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To see many other similar &nbsp;(and different) &nbsp;solved problems, &nbsp;look into the lessons

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=https://www.algebra.com/algebra/homework/Probability-and-statistics/Solving-problems-on-Binomial-distribution-manually.lesson>Simple and simplest probability problems on Binomial distribution</A> 

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=https://www.algebra.com/algebra/homework/Probability-and-statistics/Typical-binomial-distribution-probability-problems.lesson>Typical binomial distribution probability problems</A> 

in this site.


Learn the subject from there.