<PRE><B>Question 1202550</B>
&lt;br&gt;
Here are two basic ways of solving this problem.&lt;br&gt;
(1) Using the basic definition of probability&lt;br&gt;
The good outcomes are either selecting 5 of the 10 boys or 5 of the 10 girls; the possible outcomes are selecting 5 of the 20 students.&lt;br&gt;
{{{P=(C(10,5)+C(10,5))/C(20,5)}}}&lt;br&gt;
{{{P=(252+252)/(15504)=21/646}}}&lt;br&gt;
(2) Choosing one student at a time and multiplying the probabilities that the desired outcome is obtained.  The first student chosen can be any of the 20 students; after that, the next four students chosen must be the same sex as the first.&lt;br&gt;
{{{P=(20/20)(9/19)(8/18)(7/17)(6/16)=3024/93024=21/646}}}&lt;br&gt;
ANSWER: 21/646&lt;br&gt;
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