Dear Yugam Khosla,
You can change the width of article slider module in the layout files.
Example: layout-homepage.xml in "templates\sj_news25\layouts", finding:
<slideshow order="3" id="yt_slideshow">
<positions>
<position height="" width="" style="xhtml" type="modules">slide_show</position>
<position height="" width="300px" style="xhtml" type="modules">news_extra</position>
</positions>
</slideshow>
=>
<slideshow order="3" id="yt_slideshow">
<positions>
<position height="" width="" style="xhtml" type="modules">slide_show</position>
<position height="" width="" style="xhtml" type="modules">news_extra</position>
</positions>
</slideshow>
Maybe you have to change the css of article slider module at that time.
Thanks