Answer:
a.
b.
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c.
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d. It is not unusual
Step-by-step explanation:
Represent the given probability with P(T)
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<em>Solving (a): Probability two selected will live to be three years old</em>
<em>This is calculated as:</em>
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<em> --- </em><em>Approximated</em>
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<em>Solving (b): The probability that nine selected will live to be three years old</em>
<em>This is calculated as:</em>
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<em> --- </em><em>Approximated</em>
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<em>Solving (c): Probability that at least one of the nine selected will not live to be three years old</em>
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<em>To solve this, we need to determine the probability that none of the 9 selected will live to be 3 years old.</em>
<em>But first, we need to solve the probability that a selected male will not live to be 3 years old.</em>
<em>This is represented as: P(T') and is calculated as thus:</em>
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<em>The probability that none of the nine will live to be 3 years old is:</em>
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<em>So, the required probability is calculated as thus;</em>
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<em>Solving (d): Would (c) be unusual </em>
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<em>This probability is calculated in (c) above.</em>
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<em>Because it approximates to 1, we can conclude that it is not unusual</em>