Question 729509
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Approximately 70% of the Wisconsin population have type O blood. 
If 4 persons are selected at random to be donors, find P[at least one type O]. 
Round your answer to four decimal places.
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<pre>
P[at least one type O] = 1 - P[no one type O] = 1 - {{{(1-0.7)^4}}} = 1 - {{{0.3^4}}} = 1 - 0.0081 = 0.9919.


This is an EXACT value - there is no need to round.


<U>ANSWER</U>.  P[at least one type O] = 0.9919.
</pre>

Solved, with complete explanations.