Question 729623
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90% of the people surveyed believe that the speed limilt on the turnpike should increase. 
A random sample of 15 people were asked if they believe that the speed limit should be increased 
and the number who agree were recorded
1. find the probability that exactly 7 believe that the speed limit should be increased
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It is a typical question/problem on binomial distribution probability.



<pre>
The number of trials is 15, the number of successful trials is 7 
and the probability of the individual success is 0.9.


For the solution, use a standard formula


    P = {{{C(15,7)*0.9^7*(1-0.9)^(15-7)}}} = {{{6435*0.9^7*0.1^8}}} = 3.07784E-05.    <U>ANSWER</U>
</pre>

Solved.