Question 912763
<pre>
1. Chose the way to line up by gender, either BGBGBGBGBG or GBGBGBGBGB.  
That's 2 ways.
2. For each of these ways we can arrange the boys 5! ways.
3. For each of these ways we can arrange the girls 5! ways.

Solution = 2*5!*5! = 2*120*120 = 28800

Edwin</pre>