<PRE><B>Question 1180491</B>
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The problem as stated is nonsense and can&#39;t be solved.  There are an infinite number of even numbers and an infinite number of odd numbers; it makes no sense to say P(6)=1/18.&lt;br&gt;
If this is a problem about a standard fair six-sided die, then you need to say so.&lt;br&gt;
In any case, you need to define the complete finite set of numbers that the problem is about.&lt;br&gt;
Re-post defining the problem completely.&lt;br&gt;
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The reader posted a thank-you note saying he had solved the problem and the answer is k=5.&lt;br&gt;
Tutor @ikleyn posted a response saying k=17.&lt;br&gt;
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The response from tutor @ikleyn is absurd.  If k=17 and P(6)=1/18, then the probability of any odd number would be 17/18. Since 1/18+17/18=1, the conclusion from that would be that n is some odd number and the universal set the problem is working with consists of two elements -- 6 and some odd number.&lt;br&gt;
The statement of the problem says nothing about the set of numbers the problem is about; but a set of &quot;6&quot; and some odd number is unlikely.&lt;br&gt;
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What the reader did not say is that the problem is about rolling a standard 6-sided die.&lt;br&gt;
In that case, given P(6)=1/18, we know that P(2)=1/18 and P(4)=1/18, so P(even)=3/18.&lt;br&gt;
That means P(odd)=15/18; and since all odd numbers are equally likely, P(1)=P(3)=P(5)=5/18.&lt;br&gt;
So each odd number has a probability that is 5 times the probability of an even number.&lt;br&gt;
So k=5.&lt;br&gt;
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